Big Ideas Simply Explained - The History Book

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CONTRIBUTORS Philip Parker Mary Gribbin Jack Challoner Historian and writer whose books include Science writer for young readers and a Visiting DK’s Eyewitness Companion: World History, Timelines Fellow at the University of Sussex. Science writer and communicator with a of History, and Engineers. background in physics. He contributed to GLOSSARY DK’s Science and has written more than 30 Marcus Weeks Richard Beatty other books on science and technology, for readers of all ages. Writer on history, economics, and popular science. Edinburgh-based science writer, editor, and He has contributed to DK’s Science, Engineers, scientific lexicographer. Derek Harvey and Help Your Kids with Math. Naturalist and science writer for titles including Giles Sparrow DK’s Science and The Natural History Book. Popular science writer, specializing in astronomy John Farndon and space science. Popular science writer, specializing in Earth science and the history of ideas. EDITOR-IN-CHIEF CONSULTANTS SMITHSONIAN INSTITUTION Professor Robert Winston John Gribbin Smithsonian contributors include historians and museum specialists from: Robert Winston is Professor of Science and Society Science writer, astrophysicist, and Visiting Fellow and Emeritus Professor of Fertility Studies at Imperial in Astronomy at the University of Sussex. He is the National Air and Space Museum College London and runs a research program in the author of Science: A History, published by Penguin. Institute of Reproductive and Developmental Biology. The Smithsonian’s National Air and Space Museum He is an author and broadcaster and regularly writes Marty Jopson maintains the world’s largest collection of historic and hosts popular science programs, many of which aircraft and spacecraft, and its mission is to educate have been shown around the world. Previous DK books Science communicator and TV presenter, with a Ph.D. and inspire by preserving and displaying historically include the award-winning What Makes Me Me?, in plant cell biology. significant aeronautical and spaceflight artifacts. Science Experiments, and Human. Jane McIntosh National Museum of American History CHIEF EDITORIAL CONSULTANT Senior Research Associate at the Faculty of Asian The Smithsonian’s National Museum of American and Middle Eastern Studies, University of Cambridge. History dedicates its collections and scholarship to Patricia Fara inspiring a broader understanding of the American nation and its many peoples. Patricia Fara is Senior Tutor of Clare College, University of Cambridge. She has published a range of academic National Museum of Natural History and popular books on the history of science, and is a regular contributor to radio and TV programs. The Smithsonian’s National Museum of Natural History is the most visited natural history museum in the world and the most visited museum in the Smithsonian museum complex. National Museums of Asian Art The Freer Gallery of Art and the Arthur M. Sackler Gallery hold in trust the nation’s extraordinary collections of Asian art and of American art of the late 19th century aesthetic movement, and are dedicated to the acquisition, care, study, and exhibition of works in their collections.

1 2 3 2.5 MYA–799CE 800–1542 1543–1788 010 BEFORE 044 THE EUROPEAN 074 THE AGE SCIENCE BEGAN AND ISLAMIC OF DISCOVERY RENAISSANCE Features Features Features 054 Understanding Stars 016 Early Metallurgy 062 The Story of Gears 078 The Story of Anatomy 020 The Story of The Wheel 026 The Story of Geometry 084 Measuring Instruments 034 Understanding Simple 090 Medicine Machines 100 Understanding Planetary Orbits 108 The Story of Measuring Time 114 Microscopes 120 Understanding Newton’s Laws of Motion 132 Navigational Tools 146 Meteorological Instruments CONTENTS

4 5 6 7 1789–1894 1895–1945 1946–2013 158 THE AGE 230 THE ATOMIC 276 THE 350 REFERENCE OF REVOLUTIONS AGE INFORMATION AGE Features Features Features Categories 352 Measurements and Units 164 Fossils 234 Understanding 284 Understanding DNA 355 Physics Electromagnetic 358 Chemistry 170 The Story of the Engine Radiation 292 The Story of 360 Biology Oceanography 364 Astronomy and Space 174 Understanding Compounds 240 Flying Machines 366 Earth Science and Reactions 298 The Story of Space 244 Understanding Relativity Exploration 368 Who’s Who 184 The Story of Calculating 375 Glossary Machines 250 Understanding Atomic 316 Communication 382 Index Structure 398 Acknowledgments 194 Understanding Cells 326 Understanding 260 The Story of Plastics Global Warming 204 Understanding Evolution 266 Understanding 334 The Story of Robotics 212 Surgery Radioactivity 344 Understanding 218 The Story of Sound Cosmology Recording



Foreword “The past is never dead. It’s not even past.” religious festivals, while scholars William Faulkner, Requiem for a Nun, 1950 attached to mosques and monasteries deciphered God’s Modern science carries multiple designs by interpreting the natural traces of its historical origins: we world. Uneducated men and women encounter its past every day. Even were building up the practical the most sophisticated clocks mark expertise that later provided the off time in sixties, a survival from foundation of scientific disciplines— Babylonian numbering systems how to distil medicines from herbs, used many thousands of years ago. smelt ores to produce metals, Scientific heroes are celebrated in navigate by the stars, detect the units of measurement—Volts, Curies, signs of bad weather, mix chemicals Richters—and in parts of our body, to make soap. such as the Eustachian tubes in our ears. Discarded scientific theories From the earliest attempts to make live on in language: “melancholic” fires, pots, and tools, people have and “sanguine” originated in ancient always experimented to find out how Greek medicine, while “mesmerizing” the world works and how they can refers to an 18th-century French make their lives more comfortable. therapy based on magnets. Plants These twin goals of scientific research and animals still bear the Latin were spelled out in the early 17th names of Carl Linnaeus’s century by philosopher Francis Bacon. classification system, introduced in “Knowledge is power,” he declared, Sweden long before Charles Darwin’s and the rate of change accelerated as evolutionary theories made sense governments increasingly recognized of life’s complicated variety—and the advantages to be gained from rainbows have seven colors because investment in scientific projects. Isaac Newton believed they should Expanding exponentially, technological follow the mathematics of musical science rapidly came to dominate the scales worked out by Pythagoras. world, uniting it in an international web of instantaneous electronic Technological science now communication. permeates society, inseparable from political, commercial, military, and Science has uncovered many of industrial projects, yet the word nature’s secrets, but it has also “scientist” was invented only in 1833. unleashed some genies—atomic Despite that apparently late start, energy, global warming, genetic science has ancient roots. Long modification—that may ultimately before universities and laboratories destroy us. As citizens of a scientific were created, stargazers studied the global community, we need to heavens to calculate the dates of understand the past in order to control our own future. PATRICIA FARA Chief Editorial Consultant Extremophile habitat Vivid colors in the Grand Prismatic Spring in Yellowstone National Park, US, result from a film of pigmented bacteria around the edge of the hot spring. Different species of microbes flourish in specific temperatures and contain pigments suited to their environments.

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BEFORE SCIENCE BEGAN 2.5MYA–799CE Starting with early experiments to make tools and use fire, humans gradually learned how to control, explore, and understand their surroundings by developing techniques in astronomy, medicine, and mathematics.

2.5 MYA–8000 BCE The paintings at El Castillo in Spain, dating from around 41,000YA, are among the oldest known cave art. Made using natural pigments, the paintings include depictions of horses and bison, although the very earliest are abstract disks and dots. THE FIRST SIGNIFICANT SURFACE 1 upper and lower Around 1.76MYA, Upper Paleolithic leaf point SCIENTIFIC ADVANCE was the SURFACE 2 blocks rubbed more advanced stone This skillfully crafted tool was production of stone tools. Around together tools began to appear. made by flaking small pieces 2.5 million years ago (MYA), early Unlike Oldowan tools, off a larger core using a hominids (either Homo habilis surface of both Acheulian tools, or Australopithecus) began blocks heat up particularly the sharp piece of bone or to modify cobbles by striking multipurpose handaxe, antler to apply pressure. them with another stone, thus GENERATING HEAT FROM FRICTION were deliberately removing flakes of stone and shaped. Hard- core (see panel, creating a sharp edge—a Rubbing two surfaces together causes the kinetic movement hammer percussion opposite), and method known as hard-hammer energy of the rubbing motion to be transferred to the atoms in (striking off flakes a wide range of flake percussion. These early pebble the surfaces. This process, known as friction, causes the atoms to with a hammerstone) tools—such as knives, tools, or choppers, are known as heat up. The smoother the surfaces, the more heat is generated; was used to rough out spear points, and Oldowan tools. They were used in extreme cases this can cause nearby material to catch fire. the tool’s shape. It scrapers—shaped for for dismembering killed animals, was then refined by different purposes. cracking bones for the marrow, lit branches from these fires decay and extends the range removing smaller and scraping hides. Oldowan to use as weapons against of edible resources to include flakes using a soft In the late Middle technology spread throughout predators or to provide light and plants containing toxins that hammer of bone and Upper Paleolithic Africa, where it lasted until heat. There is possible evidence can be broken down by heat. or antler. (c.35,000–10,000YA), a around 1.7MYA. for sporadic controlled use The earliest evidence of new technique, indirect of fire from around 1MYA, with cooking comes from sites Mousterian tools are percussion, allowed for Early hominids must have seen evidence of regular use from such as Gesher Benot Ya’aqov particularly associated with many blades to be struck and understood the power of fire around 400,000YA. Finds at in Israel (790,000YA), where Neanderthals and occurred from a single core. The final by observing wildfires caused by Gesher Benot Ya’aqov in Israel concentrations of burnt seeds from c.300,000YA. They include stage of tool development lightning strikes. They may have (790,000YA) show signs of the and wood were found. sharp-edged Levallois flakes first appeared c.70,000YA and active use of fire. that were struck off a prepared became widespread post- sharp edge where stone glacially from about 10,000YA. flake struck off Early humans were able Making fire It involved microliths—tiny Oldowan tool to use devices such as fire Early humans probably flakes and blades for use in Choppers like this were the earliest plows or fire drills to composite tools. stone tools. They were suitable for produce their own fire made fire using a fire The earliest weapons were tasks such as cutting animal hides. with friction. Fire was drill or fire plow, rocks or handaxes, but by about important for warmth which generates 400,000BCE early people had and protection, splitting heat by rubbing adapted sticks for use as stones, hardening two pieces of wood spears. At first, these had the points of wooden sharpened wooden ends, but tools, and cooking. together. The heat by around 200,000BCE stone Heating food breaks causes wood dust points started being attached to down proteins, which to ignite and this create more effective weapons. makes it easier to digest. can then be The bow was probably first It also protects food from used to light developed around 64,000BCE, larger kindling. but the earliest examples found flame generated in kindling such as twigs c.2O.la5droMewYmAaEnaadsretloienset tools c.7co9fin0rt,Yer0ao,0’laf0loqeuYkdAnoudFvs,iareIststorBafeenlot 12fl5a,L0kepe0vr0ateolBdlooCoElimssMtmienocaauhdnsnetteiiqunrusiaEiennugbreocpoeme c.3k9na,o0twE0nl0CcBaCaEvsetEilaploral,iinSetpsintaigns, c.3fi0rs,0t 0d0omBCeEsDtiocgasted c.1.76 MYAAEcahhraelinuedlsiataxnes c.5a0n0t,l0eB0ro0txoBgoCrElosEv,eafo,ruElinensdgtlaatnd cw.4ao0toG0d,re0ön0n0isnpBgeCeaEnrO,sGl,defeorsumtnadny c.6is4,fi0r0s0t dBCeEveBloowped c.30n,e0e0d0leBsC,EfEoaurnldieisnt Ebuornoepe 12

Einkorn is the ancestor of modern wheat and still occurs naturally throughout southwest Asia. It has a higher protein content than its domesticated descendent. date from around 9000BCE. vessels, Jomon pot DEVELOPMENT OF AGRICULTURE The arrows of this period which were This style of pottery show evidence of fletching— useful for was produced in Japan The upland areas of the Fertile Crescent, an area of attaching feathers to the shaft storing food and also for cooking. for over 10,000 years. relatively fertile land in southwest Asia, were home to to improve flight and accuracy. Early pottery was generally The earlier examples wild cereals, sheep, and goats. Around 10,000BCE the formed by pinching (shaping the generally have pointed climate cooled, leading to a contraction of the range The first deliberate use of fire wet clay by hand) or gradually bottoms. of wild cereals to areas with higher rainfall. Perhaps due to to harden clay dates from around coiling rolls of clay up and into the greater difficulty in gathering the seeds of these plants, 24,000BCE, with the manufacture the shape of a pot. These pots were fired in pit-kilns, or communities began cultivating them next to their villages. Sheep of ceramic Venus figurines found bonfire kilns, which were and goats were also domesticated for their meat. More productive at Dolni Vestonice in the Czech shallow pits dug in the sources of food led to increased population densities, while the Republic. Examples of the first ground and lined with fuel. demand in time and labor needed for agriculture led to pottery vessels, from around In western Asia, unbaked clay settlements becoming both larger and more sedentary. 18,000BCE, were found in was initially used for making Xianrendong Cave in China, but bricks. The first containers were gatherers or foragers. The first barley (Hordeum vulgare)— the earliest ceramic vessels to made from gypsum and lime evidence of plant domestication were domesticated. Cultivation have survived in any quantity are plaster, which was made by (the deliberate selection and of these cereals was widely Jomon pots from Japan. These burning chalk. It was not until manipulation of plants for distributed in southwest Asia, date from about 14,000BCE and around 6900BCE that ceramic particularly in a fertile crescent were probably used for cooking pottery appeared at sites such cultivation) is of wild rye of land that stretched from food. The growing stability of as Çayönü in Turkey. seeds that were sown and the Persian Gulf to the settlements probably played The earliest bone needles harvested around the coastlands of the Near East. a role in the spread of pottery date from around 30,000BCE settlement of Abu Hureyra By 7000BCE, barley had also and come from Europe. They in Iraq around 10,500BCE. been domesticated on the stone “tortoise” core shape is may have been used to About a thousand years later, Indian subcontinent. In China, core gradually developed join skins together, using a group of wild cereals— however, a different set of threads of gut or sinew, and notably einkorn (Triticum plants, notably millet and rice, flakes are flakes are detached to thread pierced objects, boeoticum) and emmer was domesticated beginning detached from the face such as shells or beads. (Triticum dicoccoides), both in the 8th millennium BCE. Ancient clay impressions of varieties of wheat, and wild THE LEVALLOIS TECHNIQUE textiles date the first woven cloth to around 27,000BCE. This technique involves shaping a “tortoise” core using hard and Cordage—the twisting Bone shuttle soft percussion. Flakes are struck from the edges and one face together of fibers to increase Needles and shuttles of bone to produce the desired shape of the final flake, which is then the strength of the threads— were the first means of binding detached from the core. The resulting flake has a sharp edge appeared around 18,000BCE, materials together, using animal on all sides and can be used without further modification. when three-ply cord was in gut or vegetable fibers such as flax. use in the Lascaux caves of southern France. Until at least 13,000YA, early humans were hunter- c.2fi4gVu,e0rs0itn0oenBsiCc,EefoF,uiCrnszdet ccahetrDRaoemlpniuciblic c.1u8sfi,e0bgo0erfr0escaBotCtroeEdgrFaesigtrthesreet(nrtkwgnfotiohsrwt)inng c.1F4ire,s0xJta0akm0JpnoBpaomClnweEeosnsnoepf ottery c.1d0o(,ma00tey0sptBeicCoaEftFiwoirnisldtofwehienakto)rn c.8d0oom0f0geBsoCtaEitcsFaitrisotn c.18,0X0eiax0naBrmCeEvpneFldesiorsssneotglfksCpn, aofoovtwueten,nrCdyhinina c.o1f0gp,5rloa0wn0tnBdCaoEtmFAiebrssuttiHecuavirtdieoeynnra:c,eryIreaq c.1u0os,f0em0d0uinBdChbEorEuicvsikeds-ebbnuecieilndging domesct.i8c5at0i0onBCoEfFsihrsetep 13

8000–3000 BCE 15THOUSAND THE MAXIMUM NUMBER OF SOAY SHEEP ALIVE TODAY The Soay sheep is native to a small island off the west coast of Scotland. It is a primitive breed, very similar to the first domesticated sheep in Europe. ONE OF THE FIRST ANIMALS at Göbekli Tepe in southeast throughout western Europe, Farming hillsides storage. Terrace agriculture, to be domesticated by humans, Anatolia (in modern Turkey). resulting in structures such as The use of terraces to allow hilly in which flat, cultivable areas are around 30,000BCE, was the It consisted of a number of the Carnac stones in Brittany, areas to be farmed began in Yemen cut into a hillside and irrigated dog, which was selectively bred free-standing T-shaped pillars France (dating from around in about 4000 BCE but was also by water channels, was from domesticated wolves and within a low circular enclosure 4500 BCE), Newgrange Passage widely practiced in China and in developed in Yemen in around was used for hunting. Around wall. In around 8000 BCE the first tomb in Ireland (around mountainous areas of Peru. 4000BCE. In China, networks 8500BCE, people in southwest settlement wall was built at 3400 BCE), and Stonehenge of banks and ditches were built Asia began to domesticate other Jericho in Palestine. Made of in England (from 2500 BCE). Where there was insufficient to flood and drain wet-rice animals, beginning with sheep stone, the wall was about 16 ft rainfall for agriculture, farmers cultivation fields (paddies). and goats. Cattle and pigs (5 m) high with a circumference By around 6500BCE the people developed irrigation to transport were domesticated around of 1,970 ft (600 m). Architectural of Mehrgarh (in modern Pakistan) water to their fields. At Choga Cold-working (beating 7000BCE in many places across techniques became more were making bitumen, a sticky Mami, in eastern Iraq, water or hammering) of naturally the world, and by 3000BCE a sophisticated, with the use of liquid that seeps from crude oil channels from the Tigris River occurring metals, such as gold number of other animals had corbelling (overlapping stone deposits, to make reed baskets were constructed from around and copper, was practiced as been domesticated including, to create a type of vaulted roof) waterproof, and around 2600BCE 6000BCE, and by the 4th early as 8000 BCE. Smelting— in the Americas, the guinea in northwest Europe by 4000 BCE, the people of the Indus millennium BCE, dams and heating metallic ores with a pig (around 5000BCE) and the and buttresses to strengthen Civilization were using it to create dikes were used to store water reducing agent to extract the llama (about 4500BCE). walls in Mesopotamia by around a watertight coating for brick- in reservoirs in parts of western pure metal (see 1800–700 BCE)— 3400 BCE. From about 5000 BCE, built basins. In Mesopotamia Asia. In Egypt, the annual appeared as early as 6500BCE in The first large-scale the practice of building large from the 4th millennium BCE, flooding of the Nile River Çatal Höyük in Turkey. The construction of stone buildings structures using massive bitumen was mixed with sand to inundated fields naturally, but technique spread widely: it began around 9000 BCE, with the stones—megaliths—spread create a mortar for building and from at least as early as 3000BCE, was being used from southeast building of a ritual structure as a tar for caulking ships. excess water was diverted for Europe to ALLOYS The combination of two or more metals produces an alloy, which may have different characteristics from the original metals. In the mid to late 5th millennium BCE, it was discovered that smelting a small amount of arsenic with copper produced arsenical bronze, which is harder and stronger than copper alone. By around 3200BCE, true bronze was being produced in southwest Asia by using tin instead of arsenic in the smelting process, and objects such as this early 2nd century bronze figurine were being made. By the late 3rd millennium BCE, it had also been discovered that copper could be alloyed with zinc, forming brass. c.8to0Jw0en0riBwcChaEolFl, iiPrsasblteussitltoti,nnaeet c.7e0vfi0odu0ennBdcCEeaFot ifJrbastramskoeitnryIr, aq c.6co5ap0tp0ÇeBarCtEsamlEHveiöldtyeiünnkgc,,eTfoouufrnkedy c.6sp0ai0nt0dÇBlaeCtEawlEhHaorörlyileüss,ktf,oTuunrdkey c.6k0ilt0nho0sefBfiHMCraEsestPssaoouptpntpoaeetracaymur,ltiinaure c.5ca5Cn0ha0olBsgCaaErMIerarbimugiail,ttIiaroatnq cp.7ig0s0a0rBeCiEdnoCtmhaaetnetdlsNeteeiaclasnaretdeEwdahsetre c.6500 BMwCEeafiBhterirstrgutpamurrohseoe,nfidPinasfgok,risintan c.5500EbBueCrEgoipCneospainpnedsrothsumethNeelaetsaintregErnast 14

The Carnac stones in Brittany, France, are a series of more than 3,000 upright megaliths. The oldest stones date from around 4500BCE. Spinning threads “ BARLEY IS THRESHED FOR YOU, “ efficient harnesses for attaching Spindle whorls are often the first evidence draft animals to wagons were WHEAT IS REAPED FOR YOU, YOUR developed in Mesopotamia, of spinning—spun threads are wrapped MONTHLY FEASTS ARE MADE WITH allowing greater loads and around a spindle shaft. Whorls are usually IT, YOUR HALF-MONTHLY FEASTS distances to be attained. light; if heavier than 5oz (150g), they tend ARE MADE WITH IT. As commercial transactions to break the thread. Ancient Egyptian pyramid text, c.2400–2300 BCE grew more complex, accurate measurements of goods became South Asia During the early years of 5000BCE, the method of “coiling” Four-wheeled wagons appeared essential. Standardized weight by 5500 BCE; agriculture, ground for sowing pots was improved by a simple in Poland and the Balkans around and length measures were throughout Europe by had to be cultivated using turntable (tournette) beneath the 3500BCE and soon afterward in introduced in Mesopotamia, 3000 BCE; and as far as China handheld digging sticks or pot. By 3500BCE, the tournette Mesopotamia. At first, wheels Egypt, and the Indus Valley in and Southeast Asia by 2000BCE. hoes. The use of cattle as draft had been replaced in southern were solid disks connected to the the late 4th millennium BCE. The Casting metal objects with animals made the eventual use Mesopotamia by a true potter’s wagon by a wooden axle, but earliest weights were often based a mold developed in the of the ard, or scratch plow, wheel, consisting of a heavy around 2000BCE, spoked wheels on grains of wheat or barley, 5th millennium BCE. The first possible. This primitive wooden stone wheel that could be turned were developed, which made which have a uniform weight. known cast metal object plow, sometimes with a metal rapidly and continuously. This lighter, more mobile vehicles The standard unit of length, the comes from Mesopotamia and tip, cut shallow furrows. The allowed the potter to throw the possible. Around 3100BCE, cubit, was based on the length dates from about 3200 BCE. earliest evidence of its use pot by placing a lump in the of a man’s forearm. Spinning raw fibers to make a comes from the 4th millennium center of the device and shaping thread may have begun as early BCE, and it spread widely in Egypt, it as the wheel spun around. handle of pot as the 7th millennium BCE, which West Asia, and Europe. is the date of spindle whorls found For many wheel in the form of at Çatal Höyük, Turkey. Weaving The quality of ceramics was millennia, all a solid disk may have arisen from the late improved by the invention, in transportation on Paleolithic skill of making nets around 6000BCE, of kilns— land was by foot. and baskets. The loom—a frame specially built chambers in The first artificial or brace to keep one set of which pottery could be fired. aids were sleds, threads (the warp) tense while Two-chamber, updraft kilns (in which have been another (the weft) is interwoven which the fire is in the lower found in Finland dating with it—appeared in the form of chamber) appeared in the from 6800BCE, and skis, in warp beams (simple sticks) and Hassuna culture of Mesopotamia use in Russia around 6300BCE. backstrap looms (the warp beams in about 6000BCE. Around The invention of the wheel were held taut by a strap around revolutionized transportation. the user’s back) in West Asia and Egypt by the 4th millennium BCE. Wagon in clay This clay pot in the shape of a wagon dates from around 3000BCE and shows the typical features of early wheeled vehicles from central and southern Europe. c.5of0m00eBgCaEliBthusilbdeinggins c.5sm0t0oe0lStBoinCuEgtChsopAprsepiaaerds c.4m0ien0t0aMlBeoCsEbojFepicortstsat mcaarieastproduced c.4hi0lb0lus0iildBteCinEteIYrrerrmiagceaentsedare c.3w5hu0es0eeBldeCidEnFvceierhnsittcrlaelsEaurreope c.3w0em0igEe0hagBItsynCapuEdntruS,edstMsalVeneaansdrleoglaeptriyhndotitzraoemddiuac,eadndin iscu.5s0ed00inBCMEeAascrro.ed5p0dopt0olaom0mwBeiCasEtiGcuaitneedainpiPgesru c.4w5h0e0peBolCt(EtteuTrroynutirasnbienletv)teefnotred c.40c0u0ltBivCaE tWioent-birneicgCeinhsina c.350ws0ohBueCtehEleTirsrnudeMevpeeosltootppeoertd’sacimn.t3iian20a0reBCaEllCoyoeptdpreutoreambnradokneze ch.a3r1n0iean0sttsMBaCciesEhsEdodefprfivoacetfilateomtanponteiwaidmatoaglosns 15

2 .5 MYA–799 CE BEFORE SCIENCE BEGAN curved blade Metal shears Cast-iron mold adapted for Date unknown c.300 BCE harvesting grain These iron shears from Italy are similar The Chinese had invented high-temperature furnaces to those used by later sheep-shearers. capable of melting iron as early as 500 BCE. This enabled Reaping hook They were found in Riva del Garda, in them to produce cast iron by pouring molten metal into Date unknown the Italian province of Trento. molds such as this one, used to make agricultural tools. By the Iron Age, metal harvesting sickles sharp tip for piercing had replaced flint-bladed ones since the metal was readily available and easier to sharpen and mend than flint. Bronze sword flat pommel Iron sword c.1200 BCE c.500–700 Sword blades could be The Anglo-Saxons used the pattern-welding technique to blade with created using bronze, an make swords, in which rods of iron were twisted together rounded tip alloy of copper and tin. and forged to form the core. An edge was then added. Bronze Age swords, such as this one from France, were carried only by the rich. EARLY METALLURGY ANCIENT METALLURGISTS PRODUCED A VARIETY OF OBJECTS—FROM LETHAL WEAPONRY TO STUNNING JEWELRY The development of metallurgy, from around 6500 BCE, Chariot decoration made possible the production of ornamental objects of c.100 BCE–100 CE great beauty as well as tools and weapons that were Enameling, or the fusing of molten glass with more durable and effective than those made of wood. metal, was invented around 1200 BCE. The use of red glass in enameling became especially The earliest metalworking was cold-hammering—the beating of naturally occurring metals. After smelting (heating ore to extract metal) was popular in the late Iron Age, as seen in this developed, techniques became more sophisticated. Metal casting began Celtic chariot decoration. around 5000 BCE, and alloys were developed in the 5th millennium BCE. By the end of the ancient period, techniques such as gilding and inlaying had Bronze Celtic brooch been developed and metalworking had spread across much of the world. c.800 BCE This ornate brooch was created by Hallstatt craftsmen in Austria. The spiral pattern was part of the Celtic artistic repertoire for over 1,500 years. red enamel Bronze pin filigree work c.1200 Pins with flattened heads were a common decorative item used for fastening clothes in Bronze-Age Europe. bird’s head writhing snake Anglo-Saxon belt buckle granulation in profile pattern c.620 This gold belt buckle features an Gold Minoan pendant intertwined pattern of snakes and beasts, c.1700–1550 BCE highlighted in black niello—an enamel- This pendant, depicting bees depositing like substance formed from an alloy of honey on a honeycomb, exhibits granulation silver, copper, lead, and sulfur. (minute balls of gold soldered onto the surface) and filigree (fine threads of metal). 16

hemispherical iron cap Corinthian helmet c.700 BCE This helmet is made from a single piece of bronze, giving it extra strength. Such helmets were popular in Greece from the 8th to the 6th centuries BCE. rigid face decorative mask, riveted roundel to cap red glass inlay Ceremonial shield cover c.350–50 BCE Made from a bronze sheet, this shield cover displays the repoussé technique of hammering the reverse side to create a raised design on the front. stamped design Silver plaque Lydian coins c.300–200 BCE c.700 BCE This plaque depicts the figures of the The earliest coinage was produced Greek goddess Aphrodite, her son Eros, in Lydia (now in Turkey). It was made and a girl attendant, was made by from electrum—a naturally occurring repoussé. Other decorative incisions alloy of silver and gold, which was once have been highlighted with gilding. believed to be a metal in its own right. neck guard Anglo-Saxon helmet (reconstruction) turquoise c.620 eye Found in a ship burial at Sutton Hoo, UK, the original helmet was made of iron and covered with tinned bronze sheets. It was decorated with silver wire and garnets. leg shaped Bronze Age vessel Copper mask as dragon c.800 BCE c.250 This animal-shaped ritual vessel, Found in the tomb of a nobleman from Bronze figure known as yi, was used in Late the Peruvian Moche culture, this mask c.1000 BCE Western Zhou China for washing shows mastery of metal sculpture. Both This statuette of a Canaanite hands before making a sacrifice. eyes were originally inset with turquoise. god was made with a technique called cire-perdue casting, 17 which uses a single-use mold, and plated with silver using a direct application technique.

3000–1800 BCE ,,,,CLIMB UPON THE WALL OF URUK, WALK ALONG IT, I SAY; REGARD THE FOUNDATION TERRACE AND EXAMINE THE MASONRY… Epic of Gilgamesh, Tablet I, c.2000 BCE The ruins of Uruk, the world’s oldest city, are in present-day Iraq. The site of Uruk was first settled around 4800BCE and became a town around 4000BCE. IRRIGATION TECHNIQUES Mohenjo Daro and Harappa, EARLY ASTRONOMY at least 1400BCE, and in lime in a furnace, but initially BECAME MORE COMPLEX during great cities of the Indus Mesoamerica around 600BCE. was suitable only for small the 3rd millennium BCE. The Civilization, had been built. Evidence of interest in objects. In Egypt, faience shadoof was developed in astronomical phenomena Soda-lime glass was first became common from around Mesopotamia in around 2400BCE. As towns and cities developed, dates from Neolithic times in developed in Mesopotamia 3000BCE. Consisting of a mixture It consisted of an upright frame the first true writing emerged Europe, when many megaliths around 3500BCE. It was made by of crushed quartz, calcite lime, with a pole suspended from it; on in Mesopotamia around 3300BCE, were laid out in an orientation firing silica (sand), soda ash, and and soda lime, which when one end of the pole was a bucket probably prompted by the need that indicated particular lunar vitrified produced a blue- for scooping up water, while on to keep detailed records. or solar events. Some of the turquoise glaze, faience was the other was a counterweight. Originally largely pictographic, stones at Stonehenge (first used by the Egyptians on small By 1350BCE, the shadoof had with signs looking like the things erected around 2500BCE) were sculptures and beads. spread to Egypt. There, devices they represented, they were aligned to indicate the times of called nilometers had already written using a stylus that year at which the winter and The early 3rd millennium BCE been developed to measure produced wedge-shaped marks. summer solstices occurred. saw the spread of true bronze, the rise and fall of the river, Cuneiform script developed Other features may have been created by alloying copper with which predicted how good as the curved outlines of these connected with lunar events. tin, which became the most the harvest would be. early signs changed into a series commonly used metal in of wedge-shaped lines that initially primarily pictographic. Mesopotamia between 3000 and In the period 4000–3000BCE gradually became more stylized The earliest known examples 2500BCE. Clay crucible furnaces farming communities in over time. These symbols were are clay labels from Abydos, for smelting appeared there in Mesopotamia had coalesced impressed into soft clay, which c.3300BCE. Writing also around 3000BCE. Mesopotamian to form the world’s first cities, then hardened to create durable metallurgists also invented the such as Uruk c.3400BCE. By documents. At around the same developed in the Indus Valley technique of gold granulation 3100BCE, cities had begun to time, another writing system around 2600BCE, in China by around 2500BCE. This produced appear in Egypt, beginning with developed in Egypt. Known as tiny gold balls, which were used Hierakonpolis. By 2600BCE, hieroglyphic, this system was to decorate jewelry. rack for holding Egyptian boat of the dead oars in place A model of the boat buried near the Great Pyramid of Khufu. The boat shelter was intended to ferry the dead pharaoh’s soul across the heavens. high, curved c.2M9aa0sr0etaBbbCuaEilttoimn bEsgypt c.2M6oH0hab0eryBnaCtjphoEpeCDaiIatnairrdeoeusaseonsfCdtaivbilliizsahteiodn 25P5yb0ru–ai2mlt4ii7dn2sEBogCfyEGpGtizraeaatre stern Pcy.r2a6mi2s5ibdBuoCiEfltDSinjtoeEspgeyrpt c.3C0iat0ipe0psBebCaEergiinnEtogypt c.3cr0fu0ocri0nibsBMlmCeEeefCsultolrianpnyogatcaaepmspieaar c.3fa0ci0eo0nmcBmeCEobUnescieonmoEfegdsyepvtecl.o3p00se0wBCnE-pElgaynpktiasnhsips 18

1ST CENTURY THE DATE BY WHICH CUNEIFORM SCRIPT HAD BECOME EXTINCT Cuneiform (wedge-shaped) script developed from the earliest writing, invented in Mesopotamia around 3300BCE. It was used for a wide range of ancient Near Eastern languages, including Sumerian and Akkadian. Boat-building also developed had been developed in Egyptian faience of the sky into constellations the 3rd millennium BCE. The significantly around the Egypt, and by about This Middle Kingdom dates from Babylonian Akkadian Ga-Sur tablet (dating 3rd millennium BCE. Early 2500BCE, pairs of side (1975–1640 BCE) statue of manuscripts c.1595 BCE. from about 2500BCE) shows humans had probably been using oars and tillers had a woman with a tattooed the size and location of a plot some form of boat from as long been introduced. With the growing administrative of land between two hills and ago as 50,000BCE, although the body shows the deep blue demands of cities in the 3rd was probably part of a land earliest surviving water craft is Before 3000BCE, color typical of much millennium BCE, the development transaction. Fragments of a a dugout canoe that dates from few monumental Egyptian faience work. of an accurate calendar became statue of Gudea of Lagash, from around 7200BCE. In the Gulf structures were vital. The first known version is in around 2125BCE, show a plan of region, boats were being made residential. The modified by building the Umma calendar of Shulgi, a a temple. The first real street of bitumen-coated reeds as practice of building six stepped platforms Sumerian document dating from map discovered to date shows a early as 5000BCE. some temples on to create a step about 2100BCE that contains scale plan of the Sumerian town platforms began pyramid. By the 12 lunar months of either 29 of Nippur (in present-day Iraq) By around 3000BCE, more before 4000BCE, the reigns of Khufu, or 30 days. When this 354-day and dates from about 1500BCE. sophisticated vessels made of platform rising with Khafre, and year became too out of phase The first surviving attempt to wooden planks that were sewn each rebuilding. After Menkaure in mid-3rd with the real 365.25-day year, an map the entire known world together were being built in 2900BCE, temple millennium BCE, the extra month was added by royal is the Babylonian “world map” Egypt. Early boats were powered platforms in Sumerian creation of smooth- decree. The ancient Egyptians from about 600BCE, which shows solely by oars. Sailing boats, cities such as Ur and sided stone pyramids had a similar calendar, but five the regions surrounding Babylon with square-rigged sails, Kish reached a had been perfected, and days were added each year to (see 700–400BCE). appeared in Egypt in around considerable height, leading to each of these pharaohs give a 365-day year. 3100BCE, supplementing muscle the development of ziggurats— erected a huge pyramid tomb Monumentally tall power with wind power. By initially three-tiered structures for himself at Giza. Collectively There have been claims Built around 2560 BCE, the Great 3000BCE, large steering oars with a shrine on the top known as the Great Pyramids, that some prehistoric carvings Pyramid of Khufu was 482ft (147m) platform. Largely made of mud each was oriented and built with represent topographical maps, tall and remained the world’s tallest pair of bricks, with a baked-brick facing, great precision, which suggests but true cartography and real building for nearly 4,000 years. steering these monumental structures that sophisticated surveying maps were not developed until suggest growing sophistication techniques were in use. oars An interest in observational 150 in structural engineering. astronomy arose early in leaf-shaped In Egypt, most Mesopotamia, culminating 125 blade architecture was in the Venus tablet of Ammi- religious (temples) or Saduqa (dating from around HEIGHT IN METRES 100 1650 BCE). It contained the funerary (tombs). The rising and setting times of 75 tombs of the nobility and the planet Venus over a period rulers of the Early Dynastic of 21 years. A carved piece 50 Period (around 2900BCE) were of mammoth tusk found in simple mud-brick rectangular Germany, dating from about 25 structures known as mastabas. 32,500 BCE, may possibly Between 2630 and 2611BCE, represent the constellation 0 during the reign of the pharaoh Orion, but systematic division Djoser, a huge mastaba was Great St. Peter’s Big Ben Statue of Taj Mahal Notre Pyramid Cathedral Liberty Dame c.2M5eg0so0oldpBCogEtraamniualnastcioi.n2onv5fep0snri0odtBceCeoEsasErgsyapntidantislluesres poanirbsoats c.2M4et0hsf0eoopBsrCohrEtaaadimsoinioagfn, wsa aidnteveverincte producBc.tea2ab5btyh0leleo0tn,GBtiCaathEr-neuSsfieurrmstap stonecs.ib2nme5Ego0nin0ngusBlmCaaEnietmEdnS,prtteaootcrhnmttaeiaoethnngietlnauonsdlnfgoiitcaelhaarirtceeavdnednts zcig.2g2uin0ra0MtBseCsaEorFepiorbstuatimltia Sutmchaeelereinccaada.nr2lalse1irenp0,sdrt0tohaBkderCnuoEUocfmewSnmhualgi 19

2 .5 MYA–799 CE BEFORE SCIENCE BEGAN Roman 10 20 30 40 Faster armies legionary SPEED (KILOMETERS PER HOUR) Lightweight war chariots enabled armies to maneuver much Chariot faster than an infantry ever could. A Bronze Age chariot (c.1200BCE) 0 moved more than 10 times as fast as the marching pace of a Roman legionary. 50 Egyptian chariot leather bindings Around 1600 BCE, the Egyptians developed connect shaft to lightweight war chariots that had spoked wheels chariot body and a thin wooden semicircular frame. The platform could accommodate two people, one to maneuver at high speed, and another armed with a bow. wood bent ,, footboard made into V-shape to of sycamore wood make spokes …BUT LET THE LEFT-HAND HORSE hub or nave KEEP SO CLOSE IN THAT cattle intestines ,,THE NAVE [HUB] OF THE fasten spokes to hub WHEEL SHALL ALMOST GRAZE THE POST. Homer, Greek poet, from Iliad Book XXIII, first description of chariot race, c.750 BCE Neolithic period Early logrollers c.1323 BCE c.750 BCE Celtic chariot Logroller Spoked wheel Iron-rimmed wheel Neolithic people place loads Egyptian Wheels with spokes are lighter than The Celts add iron rims to the on rollers made from logs. potter disk wheels, and allow a cart or war wooden wheels of chariots to These logs, however, are chariot to be pulled by a lighter animal, improve their durability on rough not always smooth and the such as a horse. First developed in the surfaces. They do so first by nailing difficulties in keeping them steppes of central Asia a little after the metal to the rim and later, by aligned make this an 2000 BCE, these wheels spread to applying strips of hot iron, which inefficient method. Egypt by 1600 BCE. shrink to fit as they cool. 3500 BCE c.2500 BCE Egyptian c.300 BCE Potter’s wheel potter Water wheel In southern Mesopotamia, Disk wheel The Greeks invent water wheels as potters become the first to a means of harnessing the power of use wheels to mechanize an The first true transportation running water. They use water wheels industrial process—that of either to raise water in buckets to a making pottery. They use a wheels—disks of wood connected higher level for irrigation, or to drive heavy, rapidly turning stone around a shaft that operates wheel to shape clay on. by axles—are developed in the a milling machine. Balkans and Mesopotamia. The Sumerians used these on Disk wheels on battle wagons. the Standard of Ur 20

THE STORY OF THE WHEEL yoke to attach THE STORY OF horses to shaft THE WHEEL THIS SIMPLE INNOVATION HAS MOVED ARMIES, CARRIED LOADS, AND POWERED INDUSTRIES One of the most important inventions in history, the wheel allowed the transportation of loads over long distances, revolutionized early warfare, and made the development of the first mechanized processes possible. It opened up the globe to human exploration and revolutionized industry. movement box is easier The earliest wheel, the logroller, Spoked wheel construction to move was used by neolithic people to The spokes of a wheel distribute the transport heavy weights, such force applied to a vehicle evenly friction gives wheels small as large stones used in the around its rim. As the wheel rotates, outside edges turn around contact area, construction of megaliths. each spoke shortens slightly. of wheels grip static axles so friction By 3500 BCE, the logroller is less was adapted to create the outer rim on the road first true wheels—solid of wheel disks of wood connected by WHEELS AND FRICTION an axle. These wheels, spokes radiating however, were very heavy. from central hub The force needed to pull a load pressing down Lighter, spoked wheels were directly on the ground is increased by the friction invented around 1600 BCE. The more employed in Greece to harness or “rolling resistance” between the load and the hard-wearing, iron-rimmed wheels came around the power of water, via a turbine, ground. The use of wheels resolves this problem. 800 years later, making for faster, more durable for use in milling. By the time of the Since only a small part of the wheel is in contact vehicles suitable for battle and long-distance Industrial Revolution, the wheel appeared in with the ground at any one point in time, the rest transportation. Wheels steadily evolved, using one form or another in almost all industrial of it can rotate freely, without being impeded by materials such as iron and steel as they were machinery. Gears (toothed wheels) and cogs friction. The little friction that remains allows the developed. Modern wheels use high-tech alloys were used in the Antikythera mechanism—an wheel to grip the ground without sliding. Wheels of titanium or aluminum that are light and allow astronomical calculating machine created in are mounted on sturdy shafts, called axles, which vehicles to move faster, using much less power. Greece around 100 BCE—but it is possible they facilitate the rolling motion. were used earlier in China. Gears and cogs THE WHEEL IN INDUSTRY eventually became common components of Beginning with the potter’s wheel around machines as diverse as clocks and automobiles. 4500 BCE, the wheel was also adapted for use in Yet there were some cultures where the wheel industrial processes. By 300 BCE, watermills were did not feature as prominently. Some ancient civilizations of Central America and Peru did not develop wheels, or, as in the case of the Aztecs of Mexico, used them only in children’s toys. c.100 BCE “Wooden ox” wheelbarrow 1848 Gazelle steam engine 1915 1960s Mini Wheelbarrow Mansell wheel Radial tire The Chinese create a The quieter and more Patented by Arthur wheelbarrow with a large resilient Mansell Savage, radial ply central wheel, which railroad wheel has tires are made of makes all the weight fall a steel central boss rubber-coated steel on the axle. Easy to push, (hub), surrounded by or polyester cords. They each wheelbarrow can a solid disk of 16 are now the standard tire carry up to six men. teak segments. for almost all cars. Chinese spinner c.1035 1845 1910 Ford Model T 2010 High-tech racing bike Spinning wheel Vulcanized rubber tire Early automobile Modern wheel types In China, a hand-crank- Robert Thomson uses spoked wheel Ultra-lightweight operated driving wheel vulcanized rubber— Earliest automobile racing bicycles use is added to a hand- invented by Charles wheels have wooden composite carbon spindle, automating it Goodyear—to make spokes, which are spokes, while car and allowing multiple pneumatic (air-filled) more suitable for wheels are made of spindles to be operated tires, which are lighter narrow tires, but tend magnesium, titanium, simultaneously. and harder to wear out. to warp and crack. or aluminum alloys. 21

1800–700 BCE The ancient Egyptian Rhind Papyrus is based on an original text written before 1795BCE. It contains a series of mathematical problems and their solutions, including calculations of the areas and volumes of geometrical figures. IN THE EARLY 2ND MILLENNIUM ,, ANOTHER REMEDY FOR Stick chart BCE, the composite bow was Made by Marshall Islanders developed, probably in the ,,SUFFERING IN HALF THE HEAD. THE in Micronesia, this chart steppes of Central Asia. Unlike uses sticks to represent self bows made of a single piece SKULL OF A CATFISH, FRIED IN OIL. currents and waves, a of wood, the composite bow was ANOINT THE HEAD THEREWITH. technique that may have been passed down from made of laminated strips of horn, Ebers Papyrus 250, Egyptian medical treatise, c.1555 BCE ancient Polynesians. wood, and sinew, which together India, where the provided greater range and Steppes to China, where they depictions of surgery have been earliest evidence of ironworking is penetration, and allowed the bow were used during the Shang found on temple walls, but most thought to date from around 1300BCE. to be smaller and easier to use on (1766–1126BCE) and Zhou knowledge of ancient Egyptian Until medieval horseback. The bow was further (1126–256BCE) dynasties, and medicine comes from papyri times, smelting in the West produced modified to become recurved, west into Egypt and Mesopotamia. written around 1550BCE. These only bloom that needed to be hammered to remove impurities. with the ends curving forward, There is evidence that doctors show that medicine had moved It was only in China that furnaces capable of melting iron were which added even more strength. existed in Egypt during the Old beyond a belief that disease was developed and iron could be cast. Evidence of cast iron Composite bows spread from the Kingdom (c.2700–2200BCE) and a divine punishment. The Edwin production in China dates from the 9th century BCE. Smith Papyrus (c.1600 BCE) as the Rhind Papyrus. It is In mathematics, the based on a text written before air is blown in lime and crushed contains details of human Babylonians had made major 1795BCE and consists of a series with bellows to clay lining iron ore and anatomy, shows awareness advances by 1800BCE, producing of problems and solutions. It charcoal of the link between the pulse tables of reciprocals, squares, shows the use of unit fractions help raise the tuyères and heartbeat, and also gives and cubes and using them to (1⁄n), solutions for linear temperature bowl-shaped instructions for the diagnosis solve algebraic problems, such equations, and methods for furnace as quadratic equations. Several calculating the areas of triangles, tablets are thought to show an rectangles, and circles. It also and treatment of a range of awareness of Pythagoras’s shows the volumes of cylinders theorem (see 700–400BCE). The and pyramids. ailments and injuries. The Babylonians also estimated pi to be about 3.125, close to the The earliest boats recovered Ebers Papyrus (c.1555 BCE), actual value of about 3.142. date from before 6000BCE, but Most of what is known of ancient early navigation was not dating from about the same time, Egyptian mathematics comes sophisticated. The most from mathematical texts such effective navigators of this includes descriptions of diseases, period were the Lapita people of the Pacific (ancestors of the tumors, and even of mental Polynesians), who from 1200BCE expanded eastward to Vanuatu, SMELTING disorders such as depression. New Caledonia, Samoa, and Fiji. The earliest intentional Their voyage to Fiji involved a 530 miles (850km) journey production of iron was in across open sea. To accomplish Pure iron melts at 2800°F (1540°C), higher than early technology Anatolia in Turkey, which was could achieve, so instead it was smelted by reducing iron ore exporting small quantities of with charcoal at around 2200°F (1200°C). The ore was packed with iron by the 19th century BCE. charcoal in bowl furnaces, and tuyères (clay nozzles) were used At first, iron was smelted only to blow air in to raise the temperature. The resulting molten on a small scale, but by 700BCE metal was cooled to form a “bloom,” a solid lump containing iron production was widespread in and various impurities, which was then hammered repeatedly to Europe. Smelting also developed remove the impurities and extract the iron. independently in a number of places, including Africa and c.1p8rto0ad0bfuolBecrCesEqtmuBhaaaadbttrhyianleotcminlcuiaaedtnqiecsuasalotliuontisons c.1D8ep0vr0eaollBtopoCphE-mSabienenattiitcoicfscript 17D0e0pvr–eao1llto6pop0h-m0CabaBeenCnEtatiaconfsictreipt c.1p6rPo0da0oupfBcyCherEuuEEmsdg,awycnpoitnnaiatnSanamistnoiitnmhgydetails c.1a5dm0va0oanfdBcCetehEisenSsihtgthaanerrinfitdecteosavsnbetelopment 13o0f0U–g1a2r0it0icBCaElpDheavbeelotipcmscernitpt c.1p2em0op0valokBetyCehbEaelegoLPgenaisagpnciasttiacfioercaoOsscean Develocpocmm.1e8pn0ots0oiBtfeCtEhbeow c.m17a9th5eBpmCrEaoEtdigucyacpeltpiRaahnpisynrdus Laprrgoed-icuns.1ccE6taig0loey0npgBtblNCaaeEensgasdinrtshEeast c.1555 BpCrEmoEadeguddyceipcesPtaciEalarbpcnipeoystnrrisuodnsit,ioofns insdmecp.e1el3tni0nd0geBndCteElyvIerinolonIpnsdicad.1e2v0egl0loaBpsCseE ncMlaoymicseeonlnlainneéganiansnladys 22

An Assyrian bronze relief of the mid-9th century BCE shows war chariots carrying soldiers to assault the city of Khazazu (present-day Azaz, in Syria). this, the Lapitan sailors must crouching The invention of the spoked 1700 1539 Melting point have used knowledge of winds, lion cub wooden wheel around 2000BCE, 1350 1083 1064 of metals stars, and currents. They may along with the domestication 1000 Iron melts at also have created stick maps, poppy pods of the horse, opened up new MELTING POINT (°C) 950 a far higher like those later used by in crown possibilities in land transport, temperature the Polynesians who 700 than other metals settled as far as clay figure permitting lighter vehicles used in early Easter Island, glazed with and eventually the use of 350 328 metallurgy. Hawaii, and quartz and adaptable riding animals. 232 China was first (by 1000– metal oxides Although harnesses to master the 1200 CE) were in use from the technology to New 3rd millennium melt iron. Zealand. BCE, significant advances began 0 In Egypt and the Iron Copper Gold Bronze Lead Tin Near East, glass began to be to be made from c.1500BCE. made in significant amounts The halter yoke, with flat straps METALS from about 1600BCE. In the late across the neck and chest of the 2nd millennium BCE, the animal, made horses more preserving bodies in the desert sophistication around 1000BCE. technique of bonding glass to efficient at pulling light chariots. sand. These corpses were Bodies were mummified by ceramics to produce glazes Weighing as little as 66lb (30kg), wrapped in linen bandages removing the internal organs was discovered. Glass cloisonné these chariots could carry two dipped in resin, which also helped (apart from the heart), washing inlays and enameling (fusing warriors and became crucial to to prevent the bodies from out the body cavity, and packing glass to metal surfaces) were many Near Eastern armies. decaying. By around 2700BCE, it with natron for 40 days to dry developed by the Mycenaeans in the Egyptians had discovered it out. The natron was removed Greece around 1200BCE. Casting The preservation of corpses that natron (a mixture of salts) and replaced with clean packets glass (by pouring molten glass had its origins in the natural desiccated flesh and could be of natron and linen soaked in into a mold) was discovered in process of drying out and used to mummify bodies. They resin to restore the body’s shape Mesopotamia around 800BCE. gradually refined this process before being coated in resin and Around 100 years later, the until it reached a peak of bandaged in linen. Phoenicians had developed clear glass. EARLY SCRIPTS Snake goddess The transition from symbolic scripts to an alphabetic one, where Proto-Sinaitic Faience reached its peak in each individual sign represents a sound in the language, seems to symbol for the the Minoan civilization, with have first taken place among miners in the Sinai desert of Egypt letter D works such as this goddess around 1800BCE. The signs appear to derive from Egyptian hieratic statuette (c.1700BCE), but script (a cursive script that developed alongside the hieroglyphic Proto-Sinaitic with more available glass, system), but there are few inscriptions in this proto-Sinaitic symbol for the faience was replaced by alphabet and it is not certain whether slightly later alphabets in letter H glass-glazed ceramics. the region, such as proto-Canaanite (17th century BCE) and Ugaritic (13th century BCE), derived from it or developed separately. By Proto-Sinaitic 1050BCE, proto-Canaanite had evolved into the Phoenician script symbol for the that is the ancestor of Greek and other European scripts. letter K c.1o0fa5flu0pllhByCaEdbeAevtpeipcloespacerradipnPtcheoenician c.1s0mc0oe0NmltBeimCnaEgroInErboaeinnscottmhees c.9ir0oi0nn–Ci8sh0fiin0rasBtCEprCoadsutced c.8D0eG0vreBelCoeEpkmalepnhtaobfetthe c.7d0eiv0meBiltCoaEptiPcnlhgeoareorncgikclaicasrnsyss, tal ct.e1c0ph0en0maiBqkuCuoEmefEsmsgroyiepfipahctciaihsattnitiochnaetiiron c.800 BCfiErCsatspMtregosdlaouspcsoetidsaimnia c.w70id0eBsCpEreIarodnascmroeslstiEnugriospe 23

700–400 BCE The School of Athens fresco by the 16th-century Italian artist Raphael contains idealized depictions of a number of Greek thinkers, including Pythagoras (left, holding a book). AS EARLY AS 2300 BCE, the around 250BCE, but it was showed Earth surrounded cuneiform inscriptions Babylonians had developed probably first invented much by a great ocean. Hecataeus a sexagesimal number system earlier, in the 7th century BCE of Miletus (c.550–480BCE) also Salt Sea (based on writing numbers in under the rule of King drew a map to accompany Ancient map multiples of 60) and the principle Sennacherib of Assyria to water his Survey of the World This Babylonian of position (where numbers his palace gardens at Nineveh. that showed three great map from around in different positions represent continents, Libya (Africa), 600 BCE shows the relationship different orders of magnitude). By the 1st millennium BCE, the Asia, and Europe. between Babylon and other By 700BCE they sometimes used Babylonians had begun to make important places in West Asia, a marker to indicate a null maps of larger areas. By around The first evidence of including Assyria and Urartu. value (zero). 600BCE they had produced a scientific (as opposed “world map,” which showed to supernatural) The screw pump (or Archimedes the city of Babylon in relation thinking about the Screw) is a cylindrical pump with to eight surrounding regions. nature of the world a central shaft surrounded by The first known Chinese map, came from ancient inner blades in the shape of a found on an engraved bronze Greek philosophers in spiral and encased in wood. As plaque in the tomb of King Cuo the 6th and 5th centuries the shaft is rotated, water is of Zhongshan, was a plan of the BCE. Thales of Miletus pulled up the spiral, transferring king’s proposed necropolis. (b. c.620BCE) believed it from a lower to a higher level. that water was the The invention of the pump is The ancient Greek cartographic fundamental material traditionally ascribed to the tradition began in Ionia in the of the universe, and ancient Greek mathematician 6th century BCE. Anaximander that earthquakes Archimedes (287–212BCE) in (c.611–546BCE) is said to have happened when drawn the first world map that the surface of Earth rocked on the watery Archimedes Screw rotation surface on which it A hollow cylinder with rotors in the shape of shaft floated. In contrast, of a spiral inside, the screw pump pulls Anaximander, who water upward. The original version was also from Miletus, would have been turned by foot. believed that the prime material of the universe spiral-shaped was apeiron, a substance rotors move that preceded air, fire, and water. He also put forward an water up shaft early evolutionary theory, suggesting that humans had water expelled developed from a type of fish. from top The first atomic theory was water collected also proposed by a Greek, the from bottom philosopher Democritus of city of Babylon 70a0mnBuCaElrlBkvaeabrluytloeonr(zeiaepnrrose)suesnet a 60p0rsoBhdCBoEuawBcsbeuainyrbalgroyo“lntouwhnaneoindarcdilnnidtsegyimgorehfagtpi”ons c.5p5utt0hseBfCooErrAywnoaafrxdeivmaonalunetdaireolrny c.5d3etv0hereBliCograEphassPtti-Pyotahytsnhtehogatflaghetgodehrooeatrrrsaseiasimd’nsegastlhbeoeo,fuonartoewmknown c.5p8u0tBsCfmEoTrawhteaawrlreidaastlteohorfefiMtsidhiteleheaetuutnbhsiaavsteircse cp.u7Am0ric0pnhB,uiClmasEteeCedybrleyiknsAndSosrpcswiucrynearmiwlaapsn, wissatoter c.5a30wBaCtEeErutuphnaillnlisneiodl sethboruoniulSdgashmaos 24

0.65MILES THE LENGTH OF THE TUNNEL OF EUPALINOS AT SAMOS The Tunnel of Eupalinos, built in the 6th century BCE, may have been excavated accurately by surveying a series of right-angled triangles above ground. Abdera (460–370BCE), who PLATO (424–348 BCE) earlier, Chinese mathematicians scriptures called the Vedas— The Maya of Mesoamerica postulated that matter was also invented magic squares— completed c.500BCE—contain developed a complex calendrical made up of an infinite number One of the most influential of square grids of numbers in references to using astronomical system based on a series of of minute, indivisible particles. the ancient Greek philosophers, which the numbers in all rows, observations for calculating the cycles based on the number 20, Plato proposed a type of ideal all columns, and both diagonals dates of religious ceremonies which may initially have been The most famous society ruled by philosopher- add up to the same total. and identifies 28 star patterns developed by the Olmecs (the mathematician of the ancient kings, and espoused the in the night sky to help track first major civilization in Mexico) world was the Greek, Pythagoras importance of ethics as a guide By around 530BCE, Greek the movements of the Moon. before the 5th century BCE. The of Samos (c.580–500BCE). to a just life. In his many works, surveying expertise had advanced Mayan Haab (year) had 18 months He established a school that he set out a theory of ideal sufficiently to allow the engineer In the 5th century BCE, Greek of 20 days plus one of five days— promoted the mystical powers “forms,” of which the material Eupalinos of Samos to excavate thinkers moved away from one of the two elements of the of numbers and particularly of world is only a reflection. Most a water channel 0.65 miles simple cosmological theories Calendar Round cycle. Mayan the tetraktys, the perfect of his books are cast in the (1.04km) through a hillside toward more sophisticated astronomers also oriented arrangement of 10 as a triangle form of dialogues by his by digging tunnels from each ideas about the nature of the monuments to sunset positions of four rows. He is best known teacher Socrates. end. The two tunnels met almost universe. Heraclitus (c.535– at the equinoxes and solstices, for the theorem bearing his perfectly in the middle. Eupalinos 475BCE) sought to explain and were able to predict eclipses. name (see panel, below), but Zhou Bi Suan Jing (some parts may have used Pythagoras’s phenomena in terms of flux and he also firmly believed in the of which date to as early as theorem to survey right-angled change. He also believed in the The cities of the Indus Valley transmigration of souls and 500BCE), contain proof of triangles above ground to unity of opposites, saying “the were laid out in a grid pattern his followers lived by a strict set Pythagoras’s theorem. At about determine the path of the channel. road is the same both up and around 2600BCE, but the first of rules, including a prohibition the same time, or possibly down.” Empedocles of Acragas person to theorize urban on eating beans. Indian astronomy is thought (494–434BCE) believed that all planning was Hippodamus of to have its roots in the Indus matter consisted of varying Miletus (493–408BCE). He is said The oldest major Chinese Civilization. Ancient Hindu sacred proportions of earth, air, fire, to have devised an ideal city for mathematical treatise, the and water. This theory of four elements 10,000 citizens, laid PYTHAGORAS’S THEOREM remained out on a grid. Using influential for his “Hippodamian The theorem of Pythagoras a2 + b2 = c2 many centuries. grid,” he also laid out states that the sum of the 9 + 16 = 25 Piraeus, the harbour squares of the two short Mesoamerican town of Athens, and sides of a right-angled cb calendrics Thurii in Italy. triangle are equal to a This Zapotec stele the square of the from Monte Albán glyph for Zapotec hypotenuse (the long b2 = 16 in Mexico dates year “Four side). Although associated from 500–400 BCE Serpent” with the Greek mathematician a2 = 9 and contains some Pythagoras, the theorem was of the earliest glyph for known to the Babylonians around calendary glyphs Zapotec day 1800BCE and possibly also to the from Mesoamerica. “Eight Water” Egyptians as early as 1900BCE. c.5of0hM0isBilCmeEtuaHpsepocarfottadheueucwsesorldc.5m0ian0tvhBeCenEmtCamhtiiacngieaiscnessquares c.5of0Ct0hhZBeihCnEfioerEussaeBtrmiklySnaueotlawhenenmmJmeinanagttijs—ocaralrtereparotcid.s5suea0c—ac0esrdBeVCdeEdsAacnrscipaietruenrtceHosminknpdluoewtend 45d1efBsoCirgEnPHsiirptaopewoudnsagmruids c.4of2fiA0rbBsdCtEearDtaoempmrioocpctorhiseteuossrythe theoriiznecas.5tc0ho0antBstCthaEenHtuesnrtaiavcteleirtsouefsflisux 50s0Ate–llb4aá0efin0eriBsrnCetEMckoDtneefaxodwniwcazrontia,tnMteMbetxeoeneaanssmdrtoeianpatgmleesserinica 450 BfoCEwoEafrmfdopuheridseotlchelemeosernyts puts 25

2 .5 MYA–799 CE BEFORE SCIENCE BEGAN THE STORY OF 4 triangular faces arranged GEOMETRY in same plane ONE OF THE OLDEST BRANCHES OF MATHEMATICS, GEOMETRY IS EXPANDING INTO NEW AREAS The term “geometry” derives from ancient Greek words meaning “Earth 6 edges measurement,” but this branch of mathematics encompasses more than Tetrahedron map-making. It is about relationships between size, shape, and dimension— and also about the nature of numbers and mathematics itself. Geometry first arose as a series of ad hoc rules BREAKTHROUGHS IN UNDERSTANDING Octahedron and formulas used in planning, construction, and Throughout medieval times, philosophers mathematical problem-solving across the and mathematicians from various cultures 12 edges ancient world. Greek philosophers such as continued to use geometry in their models of Thales, Pythagoras, and Plato were the first to the Universe, but the next major breakthrough 8 triangular faces recognize geometry’s fundamental relationship did not come until the 17th century, with the to the nature of space, and to establish it as a work of French mathematician and philosopher field of mathematics worthy of study in its René Descartes. His invention of coordinate own right. Euclid, probably a student of Plato systems to describe the positions of points and a teacher at Alexandria, summed up in two-dimensional and three-dimensional early Greek geometry in his great work space gave rise to the field of analytical The Elements, written around 300 BCE, and geometry, which used the new tools of established fundamental mathematical and mathematical algebra to describe and solve geometrical problems. scientific principles through complex Descartes’s work led to more exotic forms of geometrical models geometry. Mathematicians had long known that developed from a there were regions, such as the surface of a handful of simple sphere, where the axioms of Euclidian geometry rules or axioms. did not hold. Investigation of such non-Euclidian geometries revealed even more fundamental Axioms of geometry principles linking geometry and number, and in Euclid’s approach to 1899 allowed German mathematician David geometry had a huge Hilbert to produce a new, more generalized, and lasting influence set of axioms. Throughout the 20th century, on later mathematicians. and into the 21st, these have been applied to a huge variety of mathematical scenarios. c.2500 BCE Pyramids at Giza 360 BCE c.400 CE 1619 Practical geometry Platonic solids “Archimedean” solids Kepler’s polyhedra Early geometry is These five regular, convex polyhedra Greek mathematician German driven by the need to (solids with several sides) are long Pappus describes mathematician solve problems such known, but Plato now links them to 13 convex polyhedra, Johannes Kepler as working out the ideas about the structure of matter. comprising regular discovers a new class volume of material They comprise five shapes that can be polygons of two or more of polyhedra known required to build formed by the joining together of types meeting in identical as star polyhedra. a pyramid. identical faces along their edges. vertices or corners. c.500 BCE Theorem of Pythagoras 4th century BCE Pair of 9th century Mosaic at Alhambra Pythagoras Geometric tools compasses Islamic geometry The Greek philosopher The hugely influential philosopher Mathematicians and astronomers lends his name to the Plato argues that the tools of a true of the Islamic world explore formula for calculating geometrician should be restricted the possibilities of spherical the hypotenuse (long to the compass and straight geometry; geometric patterns side) of a right-angled edge, and so helps establish used in Islamic decoration at this triangle from the lengths geometry as a science rather time show similarities to modern of its other two sides. than a practical craft. fractal geometry. 26

THE STORY OF GEOMETRY Platonic solids There are only five convex polyhedra (solids having several sides) that can be formed by joining identical polygons (shapes with three or more sides). Known as the Platonic solids, they are the cube (hexahedron), tetrahedron, octahedron, dodecahedron, and icosahedron. 6 square faces 12 edges Hexahedron (cube) Dodecahedron Icosahedron SPHERICAL GEOMETRY Kepler’s polyhedra 12 pentagonal ,, So-called “spherical geometry” allows the Möbius strip faces calculation of angles and areas on spherical surfaces, such as points on a map or the 20 triangular positions of stars and planets on the imaginary faces celestial sphere used by astronomers. This system does not follow all Euclidean rules. 30 edges 30 edges In spherical geometry, the three angles in a triangle sum to more than 180 degrees and parallel lines eventually intersect. ,,LET NO ONE DESTITUTE OF GEOMETRY COME UNDER MY ROOF. Plato, Greek philosopher and mathematician, c.427–347 BCE Z 1637 20th century Analytic geometry (x,y,z) Fractal geometry René Descartes’s influential work Computing power allows fractals— La Géometrie introduces the idea xz equations in which detailed y that points in space can be measured Y patterns repeat on varying scales— with coordinate systems, and that X to be illustrated in graphical geometrical structures can be form, producing iconic described by equations—a field Cartesian images such as the Mandelbrot known as analytic geometry. system famous Mandelbrot set. fractal 1858 1882 Present day Topology Klein discovery Mathematicians become Investigating geometries Computerized proofs fascinated by topology—edges with more than three and surfaces, rather than dimensions, German Computer power solves specific shapes. The iconic scholar Felix Klein Möbius strip is an object with discovers a construct problems such as the a single surface and a single with no surface continuous edge. boundaries. four-color theorem (only four colors are needed to distinguish Modern between regions of even Klein bottle complex maps). Four-color map 27

400–335 BCE Euclid’s Elements is one of the most important mathematical texts from the ancient world. It consists of 13 books and was originally written in Greek. ,, IF YOU CUT OPEN THE HEAD, YOU WILL FIND THE BRAIN ,,HUMID, FULL OF SWEAT AND HAVING A BAD SMELL… Hippocrates, from On the Sacred Disease, 400 BCE Healing hands began the study of dynamics by A marble frieze theorizing that speed could be showing directly proportional to the weight Hippocrates of the body, the force applied, treating a sick and the density of the medium woman. He in which the body moved. advocated careful examination to The foundations of geometry were laid in the mid-4th century determine the BCE by the Greek mathematician underlying and father of geometry, Euclid disease. of Alexandria (325–265BCE), in his 13-book work called ASTRONOMERS IN GREECE on this theory. He claimed that from a rival school, taught that and water—to include a fifth— Elements. In it he puts forward were interested in predicting Earth rotated on an axis, which diseases were caused by residues aither—which caused the stars a set of five “geometrical the location of celestial bodies. explained the changing seasons. building up in the body and and planets to move in a circular postulates“ and nine “common This led the Greek astronomer advised that these be neutralized. motion. Aristotle modified notions” (or axioms). From these Eudoxus of Cnidus (c.408–355BCE) Greek medicine moved in a Eudoxus’s theory to explain he deduced a set of theorems, to develop a geometrical model more scientific direction when The Greek polymath, Aristotle, anomalies, adding additional including Pythagoras’s theorem, of the heavens, in which the Alcmaeon of Croton began to refined the theory of the four spheres to a total of 55. He also and that the sum of angles in a Sun, Moon, and planets moved teach that health is achieved elements—earth, air, fire, triangle is always 180 degrees. in a series of 27 concentric by balancing the elements in Elements also included spheres. He also made an the body. Hippocrates of Cos MOTION OF THE SPHERES pioneering work on number accurate estimate of the length (460–370BCE), who valued clinical theory, including an algorithm of the year at 365.25 days. At the observation, including taking Greek astronomers explained irregularities in planetary motions for the greatest common divisor. time, most Greek astronomers a patient’s pulse, applied this by theorizing that the Sun, Moon, and planets each sat in a series believed Earth was stationary at theory, teaching that imbalances of concentric spheres. The circular motion (at differing speeds) of the center of the Solar System, in the body and impurities in each sphere generated the planet’s orbits. but Heraclides of Pontus the air could cause disease. (388–312BCE) offered a variation In the mid-5th century BCE, In the early 2nd century, the astronomer Ptolemy replaced the Euryphon of Cnidus, who was spheres with circles in his model of the Solar System. c.4te0ain0ccBhtahCeuEessHbtehiopdadpitysoiemccarabasnateelasnces c.3pu9ot0fs–ifd3oe5raw0laBfCrodErPmthlsaettoheory c.3of5EP0aoBrnCtEthuHrsoettreaaatceclshideoesnstihtsataxis 38t7heBCAEcPaldaetomfyoaustncAhdtsohoelns of cC.n3ti7dh5ueBsocCredEyleeEovsufetdmlioaopolxstsuiposhhniseorfes ctHh.3ejo5fir0tr–ssp3tr0ci0nlignBCkiEneBrD-oebanutmiflrtaovrmeksissel 350r–e3fi2nm2eosBtCtiEhoneArtoihfsetsooptrhlyeeorfes 28

334 –300 BCE 14 THOUSAND THE NUMBER OF SPECTATORS THAT CAN BE SEATED AT THE THEATER IN EPIDAURUS The acoustic properties of the theater at Epidaurus in Greece, built by Polycleitus the Younger in the 4th century BCE, allowed the actors to be heard perfectly up to 197ft (60m) from the stage. GREEK MEDICINE MADE engineering was used in the SIGNIFICANT ADVANCES in the 4th century BCE after hydraulic machinery needed the dissection of human bodies was pioneered by Diocles of to raise fuel to the fire that Carystus, who wrote the first book devoted to anatomy. The burned on top by night. During foundation of the Museum, a scientific academy set up by the day, a mirror of polished Ptolemy I of Egypt (367–283 BCE), helped give rise to an Alexandrian metal or glass reflected the school of medicine. One member, Herophilus of Sun to create a warning beacon Chalcedon (335–280 BCE), identified the brain as the seat for ships. of the nervous system and made a distinction between Pythagoras had experimented arteries and veins. with acoustics in the 6th century Greek understanding of physics also progressed under BCE. Aristotle advanced his work Strato of Lampsacus (c.335– 269BCE). He rejected the idea further in the 4th century BCE by of a force pushing light objects, such as air, upward to counter Via Appia theorizing that sound consisted The first major Roman road, the Via Appia, originally ran from Rome In Europe, wooden trackways of contractions and expansions to Capua. It was gravelled; paving stones were added in 295BCE. had been used to traverse wet in the air. The Greek theater at the force that pulls heavy and marshy ground since Epidaurus used stepped rows of objects down. He argued for the existence of a vacuum and Neolithic times, but proper seats to filter out low-frequency showed that, because air can be compressed, voids must exist roads needed a strong, background noise, which between the particles of which it is made up. centralized political authority allowed actors to be heard to build and maintain them. In perfectly in the back row. 312 BCE, the Romans began to Compiled before 300 BCE, construct a vast network of the Chinese text Huang Di Pharos of Alexandria roads that bound their empire Nei Jing explains human The Pharos of Alexandria was one together. The first road they physiology and pathology in of the Seven Wonders of the World. built, which ran from Rome terms of the balancing forces It was destroyed by an earthquake to Capua, was called Via Appia. of the universe: the opposing, in the 14th century. ARISTOTLE (384–322 BCE) Roman roads were 10–26 ft but mutually dependent, thought to be caused by an A founding figure in Western (3–8 m) wide and were laid principles of yin and yang; the imbalance of yin and yang, in philosophy, Aristotle was a pupil at Plato’s Academy in Athens. out on solid clay beds or timber five elements (earth, fire, wood, the patient’s qi, and in the During his career he wrote more than 150 treatises on frameworks, filled with loose water, and metal); and qi, the five elements that had their almost every aspect of Greek philosophy and science. He flint or gravel. Sometimes they essence of which everything is counterparts in the organs of taught an empirical approach, that knowledge is gained from were bound together with lime composed. Ill health was the body and the environment. experience, and that all matter consists of a changeable form mortar and topped with paving and an unchangeable substance. 5stones, or cobblestones in cities. THE NUMBER OF The Pharos of Alexandria PLATONIC SOLIDS was commissioned c.300 BCE (REGULAR POLYHEDRALS) by the ruler of Egypt, Ptolemy I. IN EUCLIDEAN GEOMETRY It was the tallest lighthouse in the ancient world at 410–492 ft (125–150 m) high. Innovative c.3co0om0fBmAClEiesPxsaitoonnldesrmtiahyeI Pharos c.3P0oY0loytuBchClnieeEngiateGturersrebteuahciteledEspiadaurcu.3Es0lef0omrBeCgEnetEosmupceulittdrs’iscfoarlwthacer.3tdoh0rbaey0arleBsibCifsEroauTrnhydeoeMfdAublseyexPuatnmodleraimnady I c.3C3aC0llysiBzppCiptcEhhuueessroeoarsfyddtoosf extra 33fo4usBcnChEdosAortlhisientoLAtyltecheeunms c.3Zo3Fu0iwv–Ye2ahfn7oEicus0ilhnecnBcimdiCeslEaunettdtnhiioefitenscTohthfeoCourhgyinh, etse c.3of0tC0hoheBfaCbEtlcrhHaeeidennoroenaprsivhdotiheluunesstsisfieyeassttem BeFfiorusrnstedyhei3snyrt0p-eG0oflmrcoBeaCoeiuEsrcsedhteevaetilnopged tEhuedoxus BReienfostrriosetd3ud0cyeeS0CditBeneCnigpnEtpritseahsleAosfia 33t0reBaCCEthiosTifenhdgeienmcCcilhamuitndhaeelessmpelaaaMntcieoocatviloanlue c.32b0edBteCwEsecPerrinbaxeaasrgtteohrreiaedssifoaffenCrdeonvseceins Lamc.3ps0a0thcBueCsoErSdyetorvafetvlooapocsfuuam c.30u0siBemCcEpoolTffyuohiannretgdciCneatghhlcciiebnmuoseelaayaxstlsireisdntotpesnuelmsmna,ccbueeesvirnaglue c.3a0rm0 BoCrEuCsheadinbymCaeillts BefcoormmepDe3iidl0aNi0cteiaBoiClnJEkionHnfgouC—wahnlfiiiegnsrdsewgtserei—tten 29

,,300–250 BCE ,,EUREKA! I HAVE FOUND IT. Attributed to Archimedes, Greek inventor and philosopher c.287–c.212 BCE The Roman writer Vitruvius recorded that when Archimedes got into his bath he noticed that his body displaced a certain amount of water. This gave him the idea for the Archimedes Principle. MAGNETIC IRON LODESTONES compasses were iron ladles the best methods of cultivation Ctesibian pump rocker arm pivot were described in Chinese set on divining boards that for agriculture and companion The rocker arm pushes the moves pistons literature of the 3rd century BCE. pointed south. planting to combat pests. piston down on one side, water By c.83 the Chinese text Lun- creating pressure that piston forced up heng (Discourses Weighed in In Greece, Theophrastus of In astronomy, Aristarchus of closes the inlet valve and goes up and out the Balance) had mentioned Lesbos (c.370–287BCE), a pupil Samos (c.310–230BCE) rejected forces water through the the electrostatic qualities of of Aristotle and also his successor the prevailing view among early outflow tube. Reduced piston amber, which becomes charged as head of the Lyceum school in Greek astronomers that Earth pressure on the opposite goes down when rubbed. Athens, extended Aristotle’s was at the center of the Solar side opens the valve to let work, particularly in botany. System. He believed that Earth more water in. pressure At around this time, Chinese He wrote Enquiry into Plants and rotated in orbit around the Sun; pushes diviners may also have discovered On the Causes of Plants, which whether he thought the other chamber fills outlet that iron, when rubbed against a classified plants into trees, planets also orbited the Sun is with water valve open lodestone, becomes magnetized shrubs, and herbs. He also unclear. Aristarchus estimated and will point in a particular began the study of plant the comparative sizes of the reduced pressure direction. The first primitive reproduction and discussed Sun and Earth at a ratio of about opens inlet valve 20:1, and calculated water sucked in reduced pressure pressure the distance shuts outlet valve forces inlet between Earth and valve shut the Sun to be 499 times the radius an adjustable-height mirror for circumference of a circle. He of Earth. his father’s barber shop that used also produced methods for air compressed by counterweights calculating the volumes of solids, The science to move up and down. He proving that the volume of a of pneumatics developed this idea to produce the sphere inside a circumscribed was founded by Ctesibian device, a two-chamber cylinder is two-thirds that of Ctesibius of force pump that used pistons the cylinder. Archimedes was the Alexandria in the attached to a rocker to create founder of hydrostatics (the early 3rd century pressure. With the chambers of science of fluids at rest). He BCE. It is said that the device immersed in water, the showed that objects placed in one of his first rocker was moved up and down, water will displace a quantity of inventions was alternately sucking water into liquid equal to their buoyancy. one chamber and forcing it out He also developed a systematic Chinese compass of the other. theory of statics, showing how A Han-era compass two weights balance each other in the form of a Another inventor and at distances proportional to their magnetized ladle philosopher, Archimedes relative magnitude. His aptitude set on a bronze (287–212BCE) was also one of for practical applications led him plate, featuring the greatest mathematicians to develop the Archimedes screw a diviner’s of Ancient Greece. In On the (see 700–400BCE) to pump out representation Measurement of a Circle he the bilges of a huge ship he built of the cosmos. presented a method for for the ruler of Syracuse. During calculating the area and c.2of5hS0eaBlmCioEocAesrnditsertviacerlctohhpeusosry c.2w6oc0rirkoBcsfCuEaomAncfricercacrhleliecmnuceleadtaeinnsgdtahreea ThLeeospccbh.lo3arsa0sss0stitBfuayCsrEptoslfatnots c.25A0letBhxCaeEnCCdttreeiassiidbbeiiauvnselopofupms p 30

249–100 BCE Erasistratus is said to have cured Antiochus, the son of Seleucus I of Syria, who was gravely ill. He identified the disease as love-sickness for his stepmother Stratonice, one of the first diagnoses of a psychosomatic illness. the Roman conquest of Sicily, in ANATOMY ADVANCED as the Sieve of Eratosthenes circled numbers crossed-out numbers 214BCE, he was employed by the CONSIDERABLY IN GREECE with (see panel, right). are primes are non-primes state to build various machines the work of Erasistratus of Cos to defend Syracuse from attack. (c.304–250BCE). He developed a Greek geometry advanced 2 3 4 5 6 7 8 9 10 This included the Claw of theory of vascular circulation, further in the late 3rd century BCE Archimedes—a type of crane in which he said that blood with the work of Apollonius of 11 12 13 14 15 16 17 18 19 20 with a huge grappling hook that passed through the body in veins, Perga (c.262–190BCE), whose could capsize enemy ships. while arteries distributed pneuma major work was entitled On 21 22 23 24 25 26 27 28 29 30 (air) to vital organs. He also gave Conics. In it he described volume of water displaced an accurate description of the the properties of the three 31 32 33 34 35 36 37 38 39 40 is equal to volume of object brain, including the cerebellum, fundamental types of conic and distinguished sensory from section—the ellipse, parabola, 41 42 43 44 45 46 47 48 49 50 heavy motor nerves. and hyperbola. He also developed load the theory of epicycles—circular SIEVE OF ERATOSTHENES Eratosthenes of Cyrene orbits rotating around a larger upthrust equal (c.275–195BCE) made the first circumference—to refine the This is a simple algorithm for finding prime numbers. Starting at 2 to weight of map of the world that featured theory of the motion of the without striking it out, strike out all multiples of 2 to the end of the water displaced lines of longitude and latitude spheres (see 400–335BCE). series. Return to the next non-struck out number (3) and without in around 240BCE. He also striking it out, strike out every multiple of 3 to the end. Repeat the ARCHIMEDES PRINCIPLE calculated the dimensions of The Romans found a way process; eventually all the non-struck out numbers will be prime. Earth by comparing the angles of bonding small stones to This states that a solid object, of shadows at noon at Alexandria produce concrete in the late 2nd using concrete was the Porticus Hipparchus also calculated the partly or wholly immersed in and Syene in Egypt, which are century BCE. By adding pozzolana Aemilia in Rome in 193BCE. length of the year to be 365.2467 a liquid, has a buoyant force on roughly the same longitude. stone (ash from prehistoric days—very close to the true value. acting on it that is equal to He yielded a figure of 250,000 volcanoes) to lime, they produced Observational astronomy was the weight of the fluid it stades—about 29,870miles a strong binding mortar. This revolutionized by Hipparchus of At this time, the Chinese were displaces. The relative density (48,070km)—which is within enabled them to build stronger Nicaea (c.190–120BCE), who made busy refining the production of of the object can be worked one percent of the true figure. and cheaper monumental a new map of the heavens that paper. The process of soaking out by dividing the weight of Eratosthenes buildings. The first structure built catalogued 850 stars. He invented and pulping textile rags then the object by the weight of the also worked out a new astronomical sighting tool drying them out on a screen to displaced liquid. The boat a simple method and surveying instrument called produce a fibrous mat for writing above can support a heavy of finding prime the dioptra that was in use until on, probably dates from the late load because it displaces numbers, known it was replaced by the armillary 3rd century BCE. Although the a lot of water; therefore, the sphere. Using the dioptra, he invention of paper is often buoyant force supporting it Basilica discovered the phenomenon ascribed to Cai Lun (50–121), is equally great. Maxentius of precession, by which stars he probably just refined this This early 4th- appear to move gradually in process and introduced new pulp century concrete relation to the equinoxes. materials, such as tree bark. Basilica was the largest building in Rome at the time. c.2of5tC0htoeBhsCceEedcEriseertrabiensrbgiuseumtlrislaufhtrmueossm c.2of4EC0ayBrrCteEhnE’serdamtimoesaetshnuesrnieoesnss Besfinogrele2-p0i0eBcCeEirCoenlttsirdeevelop c.2ex0ot0rraeBcCitEneSdtihlfvereoArmnisdleeasd c.2is0Nd0eoBvrCetEhloTAphmeedekiranicyAaarkctic c.1H6iNp0piBpcaCrareEeecqcahueudsinsesosiooxcfnerisobfesthe pcro.2p3e0rPtBeieCrsgE aAofpdcoeolslncorinciibusesescottfhioens Sc.o2u0tch0oBmACmEpleMeprxooiccttatwheemor-yoapfmkieeocelds 200 BthCEe–aN5ra0ez0ccCraeEgaMeteaodjgolirynitpyPhesru 193cBoCPnEocTrrtheiecteufisbrsbuAtuiellimdaltirniiglngiea—R—oims e of 31

100 BCE–50 CE ,, THE LAWS OF MECHANICS ARE ,,FOUNDED ON THOSE OF NATURE, AND ARE ILLUSTRATED BY STUDYING THE MASTER- MOVEMENTS OF THE UNIVERSE ITSELF.  Marcus Vitruvius Pollio, Roman architect and engineer, from Ten Books on Architecture, c.15 BCE A medieval depiction of a Vitruvian undershot waterwheel. Operated with a hand lever, the buckets fill with water as the wheel rotates and the buckets dip into a water source. The water is deposited at the top. THE ANTIKYTHERA MECHANISM time cycles, such as the 19-year ROMAN VETERINARY SCIENCE The Romans also advanced IS A COMPLEX DEVICE that shows Metonic cycle—the basis for engineering in this period. The architect Vitruvius (c.84–15BCE) the earliest understanding of the ancient Greek calendar. was the first to explain gears. Dating from around By the 1st century BCE the Roman interest in veterinary the use of siphons to lessen hydraulic 80BCE, it was recovered in 1900 Maya calendar had developed science sprang from the needs pressure in pumps. He also described from a shipwreck off the Greek a 5,125-year era known as the of farmers and also of the the Vitruvian turning island of Antikythera. Made up Long Count. Twenty tun (years) army, which had large cavalry wheel. When the wheel was turned, buckets emptied water of a series of bronze toothed made a katun, 20 katun were units. In the army, specialists into a channel at the top and filled up from a water source dials and at least 30 gears, it a baktun, and 13 of these called mulomedicus cared for at the bottom. This type of “undershot” waterwheel had is thought to have been used completed the whole era. The military donkeys and horses. probably been invented earlier, but Vitruvius may have refined to predict solar and lunar earliest known date inscribed Around 45CE the Roman it to make it more effective. eclipses and to track other in the Long Count system is writer Columella wrote Glassblowing was developed around 50BCE in Roman- driven gear rotates December 9, 36BCE; this is found extensively on the care and early terracotta controlled Syria. Glassmakers counterclockwise on a stele at Chiapa de Corzo diseases of farm animals. horse head obtained a more even flow by in Mexico. The Maya also used blowing molten glass through a a 52-year Calendar Round, tube (either freely or into a mold), rather with two elements working in relating them to the phases were the practices of his follower than just pouring it. The higher- combination—the 260-day Tzolk’in of the Moon. Themison of Laodicea, who was quality glassware that resulted led to calendar and the 365-day Haab. Around this time, the Greek the first recorded physician to the establishment of glassworks Around 90BCE Posidonius of physician Asclepiades of Bithynia use leeches to bleed patients. throughout the Roman Empire. Apamea (c.135–50BCE) used (c.129–40BCE) put forward his The Roman writer Celsus Roman glass the relative position of the star idea of the brain being the seat (c.25BCE–50CE) produced one The strong colors of this 1st-century CE Canopus, seen from Alexandria of sensation. He developed a of the most important vase from Lebanon are typical of the early driver gear rotates and Rhodes, to calculate the theory of disease based on the texts on medicine, Imperial period. clockwise size of Earth. His calculation flow of atoms in the body, a De Medicina, an was 240,000 stades, only slightly doctrine he derived from the encyclopedic GEARS smaller than the estimate of atomic theory of the 5th-century- summary of medical Eratosthenes of Cyrene (see BCE philosopher Democritus. His knowledge of the Mentioned c.330BCE by 250–100BCE). Posidonius also treatment methods were very time. In it, he gave Aristotle, the Romans calculated the size of the Moon subtle, prescribing baths and accounts of the use brought gears into common and made a study of tides, exercises. Perhaps less humane of opiates for calming use during this period in patients and laxatives waterwheels and hoists. to purge them. He Gears are made up of sets of 3 MILLION also detailed many interlocking toothed wheels. THE DIAMETER OF THE surgical techniques, They work when a larger SUN IN STADES, AS PER including the removal wheel engages with a small POSIDONIUS of kidney stones wheel and alters the speed of and how to operate a driving mechanism. on cataracts (clouding of the lens in the eye). c.8C0otnhBCmseEtAreucnchttiaikonynitshomef ra c.5is0SdByeCrvEieaGlnolsapseinsdbtblhoyewtLhineevgant 36inBsMCcEarEyipaatriLloioennsctgoCntoauinncitn.d1gVa5itotBrefuCtEvhiRuesofmodreacsnecaprirubcmehsipteucste c.1arCeeExCtmthhreiainncfiientrsgssetaaltntodbybobirliinneg c.90 BCaE cEuvpiduennccteuroef iunsCehoifna BCE PosidcoanolicufusElaaortfetAhspatahnmedesMaizoeon c.7o5f BBtCihEtheAyasntcioalmedpieisaovtdeftelhdosiepsoserayse c.45 Caotlrueamanteiimslleaaclwodrviiestereisansges dce.1s5cbroBuiCfbilEseduVsinritmvgreueayvtqiihnuuogsedadsnudcts enpcrcyoc.d2lou5pc–ee5ds0itaChEDeCemeMlesedudiscicailna c.90 32

50–75 ,,NATURE WILL NEVER FOLLOW,, PEOPLE, BUT PEOPLE WILL HAVE TO FOLLOW THE LAWS OF NATURE. Dioscorides, Greek physician and botanist, from De Materia Medica, c.50–70 An illustration of the common bilberry, traditionally used for circulatory problems, from a 6th-century manuscript of Dioscorides’s Materia Medica (Regarding Medical Materials). Moche medicine Much of what is known about The Greek geometer and sphere is spun by steam forced through This ceramic from medicine in ancient South inventor Hero of Alexandria steam power pipe and into sphere the Moche culture America comes from (c.10–70BCE) described a variety of Peru shows a examination of the ceramics of of cranes including the barulkos, bent pipe allows bung blocks doctor treating the Moche people from the late which operated using a toothed steam to escape, steam from a recumbent 1st century CE onward. These worm-gear that could not which pushes the exiting the patient. depict a variety of injured patients, reverse and which prevented sphere around cauldron including some with facial loads from slipping. He provided INDIAN MEDICINE HAD ITS paralysis, and also show the the first description of a lathe cauldron ROOTS IN THE VEDIC PERIOD for the precision cutting of filled with before 1000BCE, but in the period use of crutches, and primitive screws, and was also the first water 100BCE–100CE, the Caraka prosthetic legs for amputees. to describe the use of a wind Samhitã (Compendium of Caraka) wheel, in which the cauldron appeared as one of the earliest The first pharmacopeia rotating vanes stand Indian medical texts. The book (compilation of medicinal operated pistons highlights the importance of plants) was compiled by that made the fuel for fire clinical examination and the use Dioscorides in Greece. In it pipes of a water of careful regimens of drugs or he described over 600 plants, organ sound. Hero is diets to cure illnesses. Traditional including their physical perhaps most well known Indian, or ayurvedic, medicine properties and effects on for his studies into the came to stress the importance patients. Hugely influential, properties of steam. He used of balancing humors in the body it was used by physicians his knowledge to build an and ensuring srotas (channels) in throughout the Middle Ages. aeolipile. This is a primitive the body transport fluids correctly. The Huainanzi (Master Huainan) form of steam engine that uses is a compilation of Chinese steam to spin a hollow sphere. knowledge composed before 122BCE. It touches on a range of Hero’s aeolipile subjects, including philosophy, The aeolipile is the only known metaphysics, natural science, ancient machine operated by and geography. It is notable for steam. It makes the sphere spin by its analysis of mathematical and channeling steam from a cauldron musical harmonies, including into a hollow sphere and out of the a description of the traditional bent pipes that are attached to it. 12-tone Chinese scale. 600 THE NUMBER OF PLANTS DESCRIBED IN DIOSCORIDES’S DE MATERIA MEDICA c.5fi0rsCt hsainileisnegpmroadnuucaelsthe AftthemereSe1ada0rmi0cliaheBlCisttEtãeI,Oxnitnsdsei,caCoonmfarpaiklead c.5A0lgeHxeaaenrr-dodroirafivdeensccrriabneess c.5co0pm–h7pa0irlemDsiaotcshocepofieriridaset s c.7re0ipnClatohcleoesrRlpeoosmlsyacgnhlareosmsmpeirgelass c.50–1u0s0eRwomindanows figrlsatss thce.5s0elCf-hfienaetsheerininvegnotar c.50 Chinesersahmipssawpiptehar c.5su0tsrSeecnvogittttrhisiefihnctarratiibmoenpsatorts inBveenfot rsete7e5lyfRaorordmwsaecniagslhesing 33

2.5 MYA TO 799 CE BEFORE SCIENCE BEGAN UNDERSTANDING SIMPLE MACHINES DEVICES THAT CHANGE THE SIZE AND DIRECTION OF FORCES HAVE BEEN USED SINCE ANCIENT TIMES Mechanical devices are composed of different working parts. Among the INCLINED PLANE most important are six basic components called simple machines, which People have used simple ramps (inclined planes) mathematicians and engineers have studied since ancient times: the wheel to gain a mechanical advantage since prehistory. and axle, the inclined plane, the lever, the pulley, the wedge, and the screw. A person raising an object by pushing it up a ramp pushes with a lesser force than if the object were Greek engineer Hero of Alexandria (1st century the pivot at which those forces act. So, to being lifted directly; however, the object must be CE) was the first person to bring together the pushed along the ramp’s length, while the load simple machines, in his book Mechanica, gain a very large ”mechanical advantage” moves, vertically, a much shorter distance. although the inclined plane was not included in his account. Hero illustrated and explained (multiplication of force)—and move a heavy small effort force various devices for lifting heavy objects. Others can lift a heavy load before him had studied why these devices load—a very long lever should be used, but work—most notably, Archimedes of Syracuse distance traveled (3rd century BCE), who studied levers. Archimedes the load needs to be close to the pivot point. by the effort force worked out that the ratio between the input force (the effort) and the output force (the load) is What the ancient engineers didn’t realize is that distance traveled equal to the ratio between the distances from by the load there is always a pay-off between force and the RAMP distance—to gain a large mechanical advantage, The simplest example of an inclined plane is a ramp. A heavy load can be pushed up a ramp in a continuous the long end of the lever moves through a large motion that requires a smaller force than would be required to lift the load straight up. distance, while the load moves only a small way. axe blade (load) Similarly, using pulleys to lift a heavy load, the effort force length of rope you must pull is much greater wood splits apart HERO than the distance the Hero (or Heron) of load moves. The amount Alexandria was one of “work” done by the of the most prolific effort is the same as engineers of ancient the amount of work Greece. He is seen here done by the load demonstrating his (neglecting friction). aeolipile, an early example of the use of steam power. handle on wheel horizontal force (crank) turns in a WHEEL AND AXLE larger circle than WEDGE the axle Two inclined planes back to back make a wedge. An ax The wheel was invented in Mesopotamia around blade is a wedge, which, forced vertically into a block of wood, effort force produces a strong horizontal force. The force splits the wood—but the two pieces move only a small distance apart. load 3500 BCE. When a wheel is fixed to an axle, the two turn together; ancient engineers used wheels in axle rope lifts weight devices such as the windlass by winding ropes effort weight moves force around the axle. The mechanical advantage of a less distance the longer the inclined than the handle plane (and the shallower windlass is the ratio of the crank wheel’s radius the thread), the more turns it takes to drive to the axle’s radius—if the crank wheel has the screw home twice the radius of the axle, the effort force will inclined plane equivalent to the be doubled. Door handles and bicycle cranks screw thread are modern examples of the wheel and axle. TURNING FORCE weight SCREW Gears are interlocking A rope is pulled by an axle A screw thread is equivalent to an inclined plane wrapped wheels without axles; turned by a wheel. By making around a shaft. Turning a screw inside a material pulls it the mechanical a wheel much larger than the inward. Screws are also used to move water, grain, and other advantage is the ratio axle, it is possible to gain a bulk materials in screw conveyors. of diameters between large mechanical advantage – one gear and the next. but the handle moves through a much greater distance than the weight. 34

UNDERSTANDING SIMPLE MACHINES PULLEYS effort is LEVERS A simple pulley—a rope passed over a free-moving wheel— half the The mechanical advantage of a lever is the ratio has no mechanical advantage, because the rope is continuous. load of distances from the fulcrum (pivot) to the effort But by passing the rope underneath a pulley, the load is shared and the load. The ratio can be equal to one, or between two sections of the rope, and the effort is reduced by greater than or less than one. There are three half; in that case, the load moves half as far as the end of the types of lever, distinguished by the positions of rope is pulled. By combining two or more pulley blocks, the the effort and load relative to the fulcrum. mechanical advantage can be increased further. SINGLE PULLEY fixed pulley block fulcrum load CLASS 1 LEVER A rope passed over one pulley can A class 1 lever has the fulcrum raise a weight attached to the pulley wheel movable effort between the effort and the end of the rope. This set-up has around which pulley block PLIERS load. A seesaw is a familiar no mechanical advantage, but the rope moves example—normally, the pivot it does change the direction movement is in the center with the load of the force—and it can weight rises and effort at an equal distance, be more convenient than so there is no mechanical simply lifting the weight. advantage. However, an adult sitting close to the pivot can be lifted by a child sitting on the opposite end. load is raised load effort half as far as end of the rope rope is pulled fulcrum moves the same distance load is the HALF THE EFFORT fulcrum CLASS 2 LEVER as the weight weight of A single pulley block can be used to load In a class 2 lever, the load is the object create a mechanical advantage of closer to the fulcrum than the effort is two. If the rope is slung under the effort is—so the mechanical equal to load pulley wheel, the force is shared advantage is greater than one. between the two sections of This can make it easy to lift heavy BLOCK AND TACKLE rope either side of the pulley. weights, as in a wheelbarrow. An arrangement of two pulley blocks, one fixed and one EASY TO LIFT fixed pulley NUTCRACKER moving, is called a block and A block and tackle with more block with tackle. The mechanical pulley wheels gives an two wheels advantage is still increased mechanical two, because the load advantage. In this example, effort movement is pulled by two the job of lifting the load ropes—but pulling the is shared between four fulcrum load rope downward is sections of rope, so effort more convenient. the mechanical advantage is four. fixed pulley rope must be block pulled four times as far as the weight rises movable movable effort CLASS 3 LEVER pulley block pulley block In a class 3 lever, the effort is with two wheels closer to the fulcrum than the load, effort force is load so the mechanical advantage is half the load effort force is one always less than one. The load quarter the load moves farther (and faster) than the effort; a golf club benefits from this effect. fulcrum movement TONGS load is the load is the fulcrum load weight of weight of effort the object the object 35

75–250 ,, BEARS WHEN FIRST BORN ARE SHAPELESS MASSES OF WHITE FLESH A LITTLE LARGER THAN MICE, THEIR ,,CLAWS ALONE BEING PROMINENT. Pliny the Elder, Roman historian and philosopher from Natural History, Book VIII, 77 Pliny the Elder holds a pair of surveyor’s dividers in this medieval frontispiece of his book entitled Natural History. THE ROMAN HISTORIAN AND 3:10 Infant mortality stool and how to administer in China in the early 2nd century direction of one of eight dragons’ PHILOSOPHER PLINY THE ELDER rate in Rome intrauterine injections, and included calculating a value heads, which opened and (23–79) compiled Natural Despite medical explained the use of the for pi, the identification of 124 released a ball into the mouth History, a 37-volume summary advances, in the 1st and 2nd speculum mirror for internal constellations in the sky, and of a bronze frog below, indicating of ancient knowledge, which centuries, the infant mortality rate in examinations, as well as giving a the construction of an armillary the direction of the earthquake. he completed in 77. It contains Rome was still roughly 30 percent. detailed description of specific sphere with moving parts to In 138, Zhang Heng used the much of what we know about gynecological conditions. show the rotation of the planets. seismograph to successfully Greek and Roman science, and was the first to identify Soranus of Ephesus also He is best known for the detect an earthquake that covering mineralogy, astronomy, the optic chiasma, where the pioneered the science of construction of the earliest had happened more than mathematics, geography, optic nerves partially cross in pediatrics. His work contained seismograph, which he 400miles (640km) from the and ethnography, as well as the brain. He was also the first advice on the early care of completed in 132. It consisted of Chinese court, where he was including detailed sections on to name the pancreas and infants, including the making a bronze urn with a pendulum demonstrating it. botany and zoology. Natural made a detailed study of of artificial teats for feeding, and inside. When a tremor occurred, History is also significant melancholia (depression). accounts of childhood afflictions the pendulum swung in the In the 3rd century BCE, the because it contains the only such as tonsillitis, a variety of Romans discovered the principle references we have to the In the early 2nd century, the fevers, and heatstroke. work of earlier scientists. Greek physician Soranus of Zhang Heng’s seismograph Ephesus produced On the Zhang Heng (78–139) was Earth’s vibrations caused a pendulum in During this period three Greek Diseases of Women. This was a polymath whose work the seismograph to move, which released physicians published notable the most comprehensive work works on anatomy and diseases. on the subject from the ancient a ball from a dragon’s teeth into a frog’s In the late 1st century, Aretaeus world. In it, he described mouth, indicating the direction of Cappadocia wrote The Causes the appropriate training of the earthquake. and Signs of Acute and Chronic for midwives and Diseases, describing a vast range gave instructions crank opens of diseases, their diagnosis, for managing dragon’s mouth causes, and treatment. He was childbirth, such the first physician to describe as the use of ball both diabetes and celiac the obstetric disease. Among the other chair or ball drops conditions he dealt with were birthing into frog’s pleurisy, pneumonia, asthma, mouth cholera, and phthisis (tuberculosis), for which he prescribed trips to the seaside. In 100, Greek physician Rufus of Ephesus wrote On the Names of the Parts of the Human Body, summarizing the Roman knowledge of anatomy. He gave a detailed description of the eye, c.7P5haiDltoaeeplxmiththbotehossaothlkwmeornoinetleossgy c.1a0pM0hisHynmsoeirrca,oilaidldpnoeotonuxftsiAfi, seisa c.1S0op0rraooGnndrueugsecyekonsfepEahcpoythlsroeeicgsaiyautinsse Afotfebirwaa1ranr0bne0eylv-aIcavnroaulvliuleeutlnrm,ttartinohosonaft sreupplpaocretded dce.1so0cf0rCibAaerpesptdaaiedauobsceitaes 77 RomPalnincNohyamitsthtupeorlreaEitallednHseishrtiosry 100 RufwursitoefsEoapnthraeensaauttsiosemy wAco.l1er0xkMa0oenMnndineretcirlnasaliuepgupldhosarine’onusrodgsitmuchopaceefrleootstrroreyifa,monfgolfes dATefrvteeealrodp1lee0d0loiTnohmCehisina dmoAewracnshAu1igf0rteicnenrgreits1teh0sre0ieatpsfuolrse 36

One of the most complete of the original Roman bridges, the Pons Aelius was built by Emperor Hadrian to provide a processional route to his mausoleum (now the Castel Sant’Angelo). In its original form the bridge had eight arches. of the weight-supporting arch, Trajan’s bridge was destroyed in Ptolemy’s map a gladiatorial school, where he through the Arabic world, and used it in bridge-building. c.120 by his successor, Hadrian, The coordinates and topographic gained valuable knowledge of acquiring the popular name In around 104, the engineer who himself had several great lists in Ptolemy’s Almagest enabled human physiology and surgery. of Arabic numerals. Apollodorus of Damascus had bridges built, including the Pons maps to be composed of his view of He championed the theory constructed a great bridge Aelius in Rome in c.134. the world. This map dates from 1492. that the body had four basic Chinese mathematics had across the Danube to facilitate humors (see panel, below). made significant advances by the Emperor Trajan’s invasion The best-known works of are on mathematical geography the time Jiuzhang Suanshu (Nine of Dacia (modern Romania). Greek–Roman astronomer and astronomy. In Geography, he The Bakshali manuscript, Chapters on the Mathematical Ptolemy of Alexandria (c.90–168) gave a description of the known found in what is now Pakistan, Art) was in existence in 179. world, including coordinates for dates from around 200 and It included rules for calculating longitude and latitude (the latter contains instructions for the the area of arcs of circles and derived from the length of the computation of square roots. the volume of solid figures such longest day) and gave instructions It is probably the earliest as cones, and for the treatment for the creation of a world map. document to use a specific sign of vulgar fractions (written in the In Mathematical Compendium, for zero in the decimal system, form x/y). It contained instructions also known as Almagest, Ptolemy making it the first complete for the calculation of linear presented a star catalog with decimal notation with a single equations, including the earliest over 1,000 listed stars and 48 sign for each number value. appearance of equations with constellations. He refined the This system spread westward negative numbers. theory of the celestial spheres, introducing additional epicycles THE FOUR HUMORS to explain irregularities in the motion of the Sun and the Moon The theory of the four air and the apparent retrograde motion of certain planets, when humors stated that the body they appear to orbit in a contrary direction to other bodies in the is composed of four substances: Solar System. He was the first astronomer to convert blood, phlegm, yellow bile, and observational data into a mathematical model to back black bile. In blood, the four blood up his theories, using spherical CLAUDIUS GALEN (c.130–c.210) trigonometry to do so. His model elements of the universe fire Spring water of the Solar System remained hot Childhood wet the basis of astronomical theory (fire, air, earth, and until the Renaissance. Old age Born in the ancient Greek city water) are mixed Manhood Autumn Decrepitude of Pergamum, Claudius Galen In 169, Claudius Galen became Summer Winter consolidated the works of his personal physician to the Roman equally, while yellow black phlegm predecessors to create a single emperor Marcus Aurelius. Galen in the other bile bile scientific framework. His specialized in anatomy and had insistence on direct observation earlier worked as a surgeon to humors, one of the body cut across his view that each of the body’s organs element predominates. functioned according to a divinely ordained scheme. An excess of one humor dry cold He wrote 350 medical works. was believed to cause disease. Too much yellow bile led to jaundice, too much black bile to leprosy, and too much phlegm to pneumonia. earth c. D1a0om4veAarspctohulelsoDdbouarinludussboeaf bridge c.1o3fb4trhCiedogPneosnitsrsucAcotemiloipunlseted 12m7–oa1bkA4esl1seerxaPvastanottrdlieoormninaosyminical 16p9etGrosaAEoluemnrnaeplbleipeurhcosoyrmsMiceaisarcnus c.2m0fia0nrsButsasckprsiehpcatilcfiiocnstiaginnsfocr.2izse0ir0novTehnetewdhieneClbhainrarow Afitseirnv2e0n0teKdniinttSinygria 105 TrianidvnietCniohtniionanal dobafytpCeaaopifeLrun 132–1d3e8mZohnassnetigrsamHteeosngghraisph 179 ChSiunaenslseinhJseuiouaclzruohteniaoqtnanugisnatsfioorns c.2f0re0eDbzyiisnstgtiellipsaptiineovnneonbmtyeadds c.2a0r0mHoeraivsydceaivnvealPolrapyretdhia Aftaeprp2e0a0rcwComhitihpnaewrsatemtejubern-untkltiksgshhaetnadds 37

250–500 This 15th-century painting depicts the seven liberal arts, core subjects such as arithmetic, music, astronomy, rhetoric, and grammar that the 5th-century writer Martianus Capella established as the basis of early medieval European education. DIOPHANTUS OF ALEXANDRIA Roman surgical instruments In the 3rd century, Plotinus including divine beings, and that drink, and diets. Oribasius (c.200–c.284) founded the Ancient Roman physicians (c.205–270) created a modified numbers themselves had a form also described a sling to bind mathematical discipline of used a wide variety of surgical form of Plato’s teachings (see of concrete existence. a fractured jaw, which he algebra around 250 by instruments, including spatulas 700–400BCE) known as attributes to the 1st-century introducing a systematic notation and hooks (right), specula for Neoplatonism, which remained In line with the general trend physician Heraklas. Oribasius to indicate an unknown quantity internal examinations, and saws. influential into the Middle Ages. in the 3rd and 4th centuries for became personal physician and its power; for example, Plotinus taught that there is a gathering together the work to the Roman emperor in the equation x2—3 = 6, x2 In around 320, Pappus transcendent being (the “One”), of earlier scientists, Oribasius of Julian, but failed to save his represents an unknown number of Alexandria which cannot be described, Pergamum (c.323–400) produced patron when he was struck raised to the power of 2 (or (c.290–c.350) from which emanated a series Collections, a set of 70 volumes by a spear during a battle in squared). In his Arithmetica, compiled Collections, of other beings. These included that brought together the Persia in 363. Diophantus provided solutions an eight-volume work the “Divine Mind” and the “World works of Galen and other for linear equations (in which no that contained the Soul,” from which human earlier medical writers. Only In China, mathematicians variable in the equation is raised major results of the great souls are derived. Plotinus’s 20 of these volumes survive, continued to make advances. to a power greater than 1—as mathematicians who preceded follower Iamblichus of Apamea of which four, collectively titled Hai Tao Suan Ching, which dates in ax + b = 0) and quadratic him and also introduced novel (c.245–c.325) developed Euporista, give advice on food, from 263, contains a discussion equations (in which at least one concepts. Among these new these ideas, adding number of the variables is squared—as ideas were work on the centers symbolism derived from in ax2 + bx + c = 0). Diophantus of gravity and the volumes Pythagoras (see 700–400BCE). also made a particular study created by plane figures Iamblichus believed that of indeterminate equations, revolving. He also proposed what mathematical theorems proposing a method of solving is now known as Pappus’s applied to the whole universe, them that is now known as hexagon theorem, which states Diophantine analysis. Fermat’s that the intersections of three Raised fields Last Theorem (see 1635–37) collinear points (points along the The Maya cut drainage channels is probably the most famous same line) with three similar through swamps, heaping up the example of such an equation. points along a similar line will fertile silt to create raised fields, themselves be collinear. similar to the ones seen here. I HAVE ATTEMPTED,, TO EXPLAIN THE NATURE AND POWER OF NUMBERS BY STARTING WITH THE FOUNDATION ON WHICH ,,ALL THINGS ARE BUILT. Diophantus of Alexandria, Greek mathematician, from Arithmetica, c.250 c.2u5sse0ytrsMeatrieairrsmryaeiagcsdia,nfithgieoi,llnladncdanals c.2de5ov5fek–Pln2olop7awst0ona’PsalmoisdtoeiNndauiesfiso,epndloafwotormnism c.3co0Zm0i SpSiuuleansnZtCihheinSgun c.3A4leh0xisfiaPgnwatudhporreprieakuhsspeoaroxnnofaddpgulpoacrnneoestphoesoersem inct.r2o5d0ucDeisopahlegaqenubtuartsaioicns m2ap6trh3oedCmuhcaiSentiuecHasiaaneinCTsahoing cp.r3o0pm0oasIatehmsectbmohlniaacctthritnuceouasttemlhoteebfhxeAeeirsponstarteeihmnrmaecevesauenaaanipvdpelryse 38

,, ,,THE SHAPE OF THE EARTH IS NOT FLAT, AS SOME SUPPOSE WHO IMAGINE IT TO BE LIKE AN EXPANDED DISK… Martianus Capella, from On the Marriage of Philology and Mercury, 410–439 7THE NUMBER heliocentric view of the solar OF LIBERAL ARTS system (see 1543). IDENTIFIED BY ROMAN WRITER CAPELLA Mathematics progressed only of right-angled triangles and in decimal places (see panel, below), slowly during the later Roman around 300, Sun Zi compiled the a figure that was not improved empire. In about 450, the Sun Zi Suan Ching, which includes upon until the 16th century. Neoplatonist philosopher an analysis of indeterminate Proclus (c.410–485) produced equations. It also contains what Martianus Capella, from his Commentary on Euclid, in is now known as the Chinese Madaura in North Africa, which he preserved the work remainder theorem, which established the basic structure of earlier mathematicians. provides a method of finding of early medieval European Proclus’s contemporary, solutions to problems in education. In his On the Marriage Domninus of Larissa (c.410–480) modular arithmetic (also called of Philology and Mercury wrote Manual of Introductory clock arithmetic, because (410–439), he presented a Arithmetic, which included a numbers are arranged in a circle, compendium of knowledge, summary of number theory. rather than along the number which he divided into the trivium line). In the 5th century, Zu (grammar, dialectic, and rhetoric) By the 5th century, the Maya Chongzhi (429–500) wrote Zhui and the quadrivium (geometry, had devised a sophisticated Shu (Method of Interpolation), in arithmetic, astronomy, and calendrical system and a which he calculated pi to be 355/113. music). In this work, he stated notation system for numbers He refined this to produce a value that Mercury and Venus orbit that could express any number for pi that was accurate to seven around the Sun, a view that using only three symbols: Copernicus used to support his a dot for 1, a bar for 5, and a shell for 0. Maya astronomers THE VALUE OF PI were particularly concerned with lunar cycles, the Sun, Pi, the ratio of the circumference of a circle eclipses, and movements to its diameter, was estimated at 3.125 by of the planet Venus. the Babylonians. The Greeks discovered a method of calculating it by using the sides There is also evidence that the of a polygon inside a circle to approximate Maya were practicing raised- the circumference, and Archimedes used field agriculture from as early this method to give a figure of 22/7. In as the mid-3rd century to utilize about 475, Zu Chongzhi calculated pi as fertile land that would otherwise 3.1415926—accurate to seven decimal places. Computers have have been too waterlogged for now calculated this value to trillions of decimal places. agricultural use. Astronomical codex A section from the Dresden Codex, a 9th-century Maya astronomical work that includes detailed tables for movements of the planet Venus. c.4in0tcr0aoblTdcyhuuaeclpaoetpnsirnaoogfxmAsimqeletuaxhataoirnodednorrfoiaots c.4P5rCo0ocGmlurmseeewknrtipatehrsiylohosnisoEpuhcelrid c.4ca7dl5ceuZcliuamtCeahsloppnligatzcohesiseven c.3P6e0rgOarmibuoamnsiduwiserotitefetsics 410–439aMssaerrtitasantnuhadsartVCoMeuannpeuedrscltluahorerybSitun DmIoniwmdtrrn-oititdneousuclshatoiotsrefyML4Aaa0rrn0iitusshsamal oeftic Arymacb.ah4ta9ht9eameI(ns4atdt7itoimi6acb–niaae5tn5e30s.1)p4i16 39

500–540 ,, YET IT SEEMS NOT TO REST UPON SOLID MASONARY, BUT TO COVER THE SPACE WITH ITS GOLDEN DOME ,,SUSPENDED FROM HEAVEN. Procopius, Byzantine scholar, from The Buildings Book, c.500–65 The dome of Hagia Sophia was completed in 537 and collapsed in an earthquake in 558. It was rebuilt by Isidore the Younger, who raised it by about 20ft (6m) to make it more stable. MUCH ANCIENT KNOWLEDGE geometry and Ptolemaic BUILDING WITH PENDENTIVES reached the Middle Ages through astronomy. Without his work, the efforts of Roman nobleman much ancient knowledge might Pendentives, such as those employed domed top concave Boethius (c.480–c.524). He acted have been lost in western Europe. in the church of Hagia Sophia in section of pendentive as a link in the transmission Constantinople, are curved, concave at corner of of Greek and Roman science Flavius Cassiodorus sections of masonry that are used to building the square to scholars of his time. He (c.480–c.575), who succeeded join a square lower section of a building translated sections of Aristotle’s Boethius as the leading Roman to the circular base of a domed top supporting section of Logic, produced an adaption nobleman at the court of the section. They allow the weight of the pillars and the building of Greco–Roman mathematician Ostrogothic kings of Italy, retired dome to be equally distributed onto Nicomachus’s (c.60–c.120) around 540 to a monastery he square supporting walls or piers, which arches examples of problems involving Arithmetike Eisagoge (Introduction founded at Vivarium in southern allows far larger domes to be built. arithmetical progressions to Arithmetic), and compiled Italy. There, he composed square lower (where the difference between manuals of the liberal arts, Institutiones Divinarum et section of successive terms is constant). including accounts of Euclidean Humanarum Lectionum (An building Introduction to Divine and Human Around 532–37, Byzantine treatises were collected. He stone oysters, or stone swallows; architects Anthemius of Tralles Readings). This instituted the practice of copying they were said to emerge from (c.474–c.534) and Isidore of handbook on manuscripts, thus ensuring that the rock and fly around during Miletus succeeded in setting a monastic life important works survived into thunderstorms. By the mid-7th round dome over a square room included a the later Middle Ages. century, such fossils were being using pendentives. The dome of compilation of dissolved in vinegar for use as Hagia Sophia (in Istanbul, Turkey) secular knowledge, Before the 6th century, scholars medicine in China. remained the largest in the world divided according to had largely accepted Aristotle’s for nearly a thousand years. the seven liberal view that motion was inherent in In early 6th century, Chinese arts (see 250–500). a body or caused by the medium mathematician Zhang Qiujian grooved, shell-like Cassiodorus also through which it traveled (such gave the first example of the “bird’s wing” established a as air). Greek philosopher John modern method of division— library in which Philoponus (c.480–c.570) inversing the divisor and many ancient opposed this view, arguing that multiplying. He also gave scientific and the medium actually resisted the philosophical body’s movement. He proposed Brachiopod that motion is caused fossil Great minds externally through energy Resembling Boethius is shown impressed upon it by the person bird’s wings, here calculating or thing moving it. This was the these became known as with written numbers first expression of the theory of “stone swallows” in China. in a competition impetus and inertia. against Pythagoras, who is using a Around 500, Li Tao-Yuan counting board. recorded fossil animals in his Commentary on the Waterways Classic. He called these fossils c.5gi0ng0ewiCanirotIhintntdwoginaoursmed c.5w0op0oridFneitrnisntbguliosncekCoshfifnoar c.5re0bc0orarLdcishTiafooops-osYdiulsanin China 51w0r–air2tegi4tsehABobmrmooiseeoetttkotihcsrtilyuaeo,sn’nsadnLdogtricanslates 53r2oH–u3naT7gdusirFadqkiouSremsayot—rpeeh—isiraoisnocemhtuorvcehr, a c.5co4m0 pCoossemsaTsopInodgircaopphlieauCshtersistiana cd.e5s0c0rriZebhceoaisfpndtrghoivecQisamiiulojeonitafhundosidvinisgor Xu YuetwheritMeastMheemmaotiircsaol nArt Nahrbauw5ila3tn1in–c7Pan9earslia 540 VCIinavsisatsriiHtiouuudtmmioornaaunenssadrrDecuiotmvimrineLpaseorctusotmeiosneutm 40

541–609 2 MILLION THE ESTIMATED NUMBER OF INDIVIDUAL MOSAIC TILES ORIGINALLY USED TO CREATE THE MADABA MAP The Madaba map is a mosaic showing Palestine and lower Egypt, with particular focus on towns and other sites of Biblical importance. This part of the map shows Jerusalem. THE FIRST DESCRIPTION of the 7:10 Bubonic plague One of the leading medical CHINESE BLOCK PRINTING bubonic plague was given by death toll practitioners at the time of the Roman historian Procopius At its peak, Byzantine emperor Justinian was Printing using wooden blocks was probably invented in China in the (c.500–c.565). He was present the bubonic plague, which struck the Alexander of Tralles (c.525–c.605). 6th century, although the first complete surviving printed book dates in Constantinople (now Istanbul) Byzantine empire in 542, killed 10,000 His Twelve Books on Medicine to 868. A manuscript was prepared on waxed paper, which was when the disease struck the people a day in Constantinople alone. described a range of diseases rubbed against a wooden block to transfer a mirror image of the Byzantine empire in 542. He including those caused by characters onto it. The block was then carved and used for printing. described the characteristic Christiana (Christian Topography), intestinal parasites. He was swellings (or buboes) under the which controversially presented the first physician to identify arms and around the groin, and the world as a flat space dividing melancholy (depression) as a type of delirium brought on by the heavens from the underworld, a cause of suicidal tendencies. septicemia (blood poisoning) and in which Jerusalem occupied that caused sufferers to run a central position. Cosmas Around 570, Chinese around screaming. located Paradise just beyond the mathematician Chen Luan ocean that surrounded Earth. mentioned the abacus for the By the 6th century, the first time in a commentary on an cartographic tradition inspired earlier work of the 2nd century. by Ptolemy was waning, to be He described 14 methods of replaced by a religiously inspired arithmetical calculation, one view of Earth. The Madaba map, of which he referred to as “ball thought to be the oldest surviving arithmetic,” in which a series map of Biblical cities, dates of wires were suspended on a back to this time. In around wooden frame, with four balls 550, Cosmas Indicopleustes, strung on the lower half of each a merchant from Alexandria, wire representing a unit each, composed the Topographia and a ball on the upper half representing greatest project was the cutting Chinese engineer Li Chun five units. of the Grand Canal from completed construction of the Changan to Loyang, under Anji Bridge in Hebei. The arch Although the the Sui dynasty, which joined up was flattened by two smaller Chinese had a long earlier, smaller canals. Its main arches in its spandrels (the tradition of canal section, the Pien Chu canal, triangular area bounded by building, their which was 621 miles (1,000km) the outer curve of an arch and long was completed in 605 adjacent wall), which spread the Rainbow bridge and was said to have taken five weight more evenly and meant This bridge over a side million laborers to build. that only one main arch was section of the Grand needed to span the river. Canal at Wuxi, China, By the early 7th century, arches in a dramatic Chinese engineers had worked fashion, which gave out that bridges did not need this type of construction semicircular arches. In 605, the nickname “rainbow bridge.” c.5p5hdy0escGsirccrauireansienbdhkeiAbnsergeutiafvuosusrtlcaceapnscer c.5of6pT0sriyAnaclclelhleuxisaadtndirndeigcescrdcroeinbpderesitsisoinosn, 56S2orTpehhcaeoinanHdesataorgrmuitahcetqeiusdaakfeteinr 558 c.6pe0Uo0SpiHrAleroichgorfoaektsaioaoteumntlhnawergtewes-otsrckasle 60G5rcaConomdnpsCltearutnecadtlioinnCohf itnhaeis 54o2uPtbrroecaokpioufsbindueCbsoocnnrisicbtaepnslataignnuoeple pcr.o5p5o0sJeoshannthPeehaoirlrloyypofoofnrimunseorftia 54m2a–p6i5sMcraedaatebda imnoJsoardican c.570 First mofeanbtiaocnus 5s9u5spAenbnsuiosrioluiotntnihncwbhYerauisidnntgnCeahni,na bFriridsgt eu-sbeuoilfdsinpganindrCehlsina 605 in 41

610–700 This illustration from a 12th-century manuscript graphically depicts the use of Greek Fire. Flames are being projected from a handheld tube onto a fleet of invading soldiers. IN CHINA, in the year 610 court ,, AS THE SUN ECLIPSES THE contemporary knowledge, physician Chao Yuanfang STARS BY ITS BRILLIANCY, SO THE entitled Etymologiae, using the (550–630) compiled the first MAN OF KNOWLEDGE WILL ECLIPSE work of earlier encyclopedists comprehensive Chinese THE FAME OF OTHERS IN ASSEMBLIES such as Roman author Marcus treatise on diseases. One Terentius Varro (116–27BCE). It of the diseases he described ,,OF THE PEOPLE IF HE PROPOSES helped disseminate classical was smallpox; he explained knowledge in the Middle Ages. that lesions with purple or black ALGEBRAIC PROBLEMS, AND STILL coloration were far more deadly MORE IF HE SOLVES THEM. In the field of surgery, Greek than those that contained white physician Paul of Aegina pus. He also recommended Brahmagupta, Indian mathematician, from Brahmasphutasiddhanta (c.625–c.690) compiled The brushing teeth daily and (The Revised System of Brahma), 628 Epitome of Medicine—a digest of proposed a routine of rinsing medical treatises by ancient and gargling then gnashing Before 644, windmills had been which could be used to grind authorities such as Galen. It ISIDORE OF SEVILLE the teeth seven times. developed in Persia. They used wheat. The earliest windmills had also contained descriptions of (C.560–636) wind to drive wooden vanes set in vertical windshafts, unlike the new surgical procedures, such a circle around a windshaft. This more familiar horizontal types that as tracheotomy (surgery to the The Bishop of Seville for generated rotational energy, were later developed in Europe. windpipe) and sterilizing wounds more than 30 years, Isidore through cauterization. wrote several important texts, Spanish bishop Isidore of including the encyclopedic Seville was a prolific author who Chinese mathematician Wang Etymologiae, a dictionary of wrote books on cosmology and Xiaotong (c.580–c.640) was the synonyms, and a manual arithmetic. In the 7th century, first to provide solutions for of basic physics. He also cubic equations (of the form established a system of he compiled a 20-volume a3+ba2+ca=n). It was a technique seminaries to promote manuscript of that European mathematicians ecclesiastical education. did not master until Fibonacci He was canonized in 1598 (see 1220–49) in the 13th century. by Pope Clement VIII. In India, one of the greatest two negative numbers multiplied early mathematicians was together yield a positive number. Brahmagupta (598–c.668). His Brahmasphutasiddhanta In the late 7th century, a new (The Revised System of Brahma) incendiary weapon was developed contained rules for using in the Byzantine empire. Known negative numbers in arithmetic as Greek Fire, it was discharged and also first stated the rule that by tubes and burned even in contact with water. Its exact Vertical windmills composition is still unknown, but Because the area around Nishtafun it was probably a compound of in Persia (Iran) experienced high naphtha (a hydrocarbon mixture). winds, but had little water, windmills were a very useful adaptation. c.6tr1ec0aootCnifsthaseaimnoosnaYluddlaepisnsoecfxaarnsipegt’ison c.6d2efs5ocrWrcibaunebsgicsXeoiaqluouttaoiotninogns c.6q5uin0alvHietyingtpheodricnelCahininias c.6do5Pc0rtaooBrttyorzTesahapnetatiositnhpeeahorinliuuussrowlroigteys c.6de6cs0accnPraciabueuetrlesaorbinfzrdAaeettaihgoseitnnuainsesuorfgery c.615S–e3v0ilIlseEidctyoommreoploiolfegsiae c.628 FmiorasftthzseeermocuainrtiecInauldsteiaenxts 644mVeenrttiiocanlewd iinndPmeirlslisafi(rIrsatn) c.67B0yzGdarenevteeinlkoeFpeeirmdepinire 42

700–799 This image depicts Jabir ibn-Hayyan giving a lecture on alchemy in his home town, Edessa, modern Turkey. The town played an important role in the transmission of Greek science into the Islamic world. THE ISLAMIC WORLD’S FIRST 13As knowledge of Greek THE NUMBER OF a major Islamic center for the MAJOR TREATISES on zoology TEST SITES SET UP study of science. were produced by al-Asmai, a astronomy spread to the Islamic BY YI XING FOR HIS philologist from Basra, Iraq. His world, Ibrahim al-Fazari ASTRONOMICAL Jabir ibn-Hayyan (c.722–804) Kitab al-Khail (Book of the (d. c.796), an astronomer from SURVEY was an early Islamic alchemist Horse) and Kitab al-Ibil who has become known as the (Book of the Camel) Baghdad, wrote the first father of Arab chemistry. He described in detail Islamic treatise on the invented the alembic, an the physiology of these astrolabe—a device that enclosed flask for heating animals. He also wrote books on sheep and wild Astrolabe transferred observations of the of planetary movements, liquids, established the animals, as well as a A Greek invention refined by celestial sphere onto flat plates conjunctions, and eclipses, classification of substances book on human Arab astronomers, the astrolabe and helped predict the location although he rejected the idea into metals and nonmetals, anatomy. of celestial bodies. that Earth rotated. and identified the properties helped perform complex of acids and alkalis. pivoted astronomical In China, around 725, engineer A few years later, in 762, the sighting rule calculations. Jurjish ibn Bakhtishu was plate with and astronomer Yi Xing city of Baghdad was founded the first of a dynasty of Islamic star map (683–727) invented the first by the caliph al-Mansur. The physicians who served the escapement for a mechanical first planned city in the Islamic Abbasid caliphs at Baghdad. clock. The device was attached world, its perfectly round shape He rose to prominence when to an armillary sphere (a model was laid out by al-Naubakht, he cured the caliph al-Mansur of the celestial sphere) that was a Persian astrologer. His son, of a stomach complaint in 765. powered by water. It used al-Fadl ibn Naubakht, founded His grandson Jibril founded a toothed gear to transfer the House of Wisdom in the first hospital in Baghdad energy to the moving parts Baghdad, which became some time after 805. of the sphere and to regulate their movement. Yi Xing also carried out a major astronomical climate plate with survey to help predict AIR EARTH GOLD MERCURY TO PURIFY MAGNET coordinates to locate solar eclipses more user’s latitude accurately and reform ALCHEMY the calendar. In India, mathematician and astrologer Lalla (c.720–790) First developed in Hellenistic Egypt (4th–1st century BCE) by scholars became the first to describe a such as Zosimos of Panopolis, alchemy was advanced further by perpetuum mobile, a machine Arab practitioners such as ibn-Hayyan and al-Razi in the 8th–9th that once set in motion would centuries. It was concerned mainly with the transmutation of base carry on moving forever. His metals, such as lead, into noble metals, such as gold, through the Sisyadhivrddhidatantra (Treatise use of the “philosopher’s stone.” It led to the development of many for Increasing the Intelligence practical chemical processes, such as distillation and fermentation. of Students) also gave details Bybo7ba0oro0adnrLsdCeasehnaidnreecseuenstseehdrips c.7m0to4rneAkantBigseleod-oeSnwatxriomitneeskaeeping c.7e2smc5aeYpciehXmainneigncatinlfvocerlonctsk c.7sp5tr0oePathdaespeIfsrrloaummseCichwinoarld c.7e5stt0eaixbAntlriiSlasepbhaisncinodtutsotnry 76r5iscJeuusorrfitnjoaigspshctroaiobmlminpaihBnceahanklc-chMoetmiasanphftslueaurirnt c.7in7va5elehnIbmetsnabt-eiiHnncagcflyloflayssuaekinddfsor c.7m7da5temhIsnecodmrtiiiabaonetniscdipaeenvriLpceaeltluaal lustecr.-7ips0a0cirnCeItsaoeltldaeomdgreliiacdnswtshoerld exmhiabcgi.t7nk2en0tiocCwdhleeincdleginseeaotifon c.w75orin0tetAshlea-Fatarseztaarotriilsaebe 762 FirtshtepBIlsaalnagnmhedidcadcwi—toyrislidnb—uilta7s7tr1torSnaiondmsdlhiacataneltdtar,ienIanttodisiAaern,aisbic cartocgo7rma8pp5lheIemtmrespJaeiptahroieDaflafiCnrhsitna c.8w0r0iteAsl-otArnesazmotiaosileosgy 43

2

THE EUROPEAN AND ISLAMIC RENAISSANCE 800–1542 Classical knowledge was revived and expanded by Islamic scholars attached to the mosques and the courts. Subsequently translated into Latin, their Arabic texts circulated through Western Europe and formed the basis of modern science.

800–20 821–60 ,, FONDNESS FOR SCIENCE… HAS ,,ENCOURAGED ME TO COMPOSE A SHORT WORK ON… WHAT IS EASIEST AND MOST USEFUL IN ARITHMETIC. Al-Khwarizmi, Persian mathematician, c.780–850 The House of Wisdom in Baghdad was a major center of Islamic scholarship, attracting the foremost thinkers from across the Islamic world. THE ARABIC AND PERSIAN astrolabe—an instrument used ONE OF AL-KHWARIZMI’S ax2 + bx + c = 0 EMPIRES had a long tradition of to observe the position of stars. MAJOR ACHIEVEMENTS was a scholarship, and this continued Although not the first to produce treatise on mathematics entitled ALGEBRA after the birth of the Islamic a work on the astrolabe, The Compendious Book on religion. Islam encouraged al-Khwarizmi’s contribution Calculation by Completion and Algebra is a branch of mathematics that uses letters to represent scientific and philosophical was significant, especially in Balancing, published around 830. unknown quantities (called variables), and symbols for operations pursuits, which were not seen the Islamic world, where the It contained a description of the such as addition and subtraction. These can be combined in an as incompatible with theology. astrolabe could be used to branch of mathematics now algebraic statement known as an expression, such as “a + 3”. Libraries and other centers calculate the time of daily prayers. known as algebra. Although he A mathematical statement, such as “a + 3 = 7”, is known as an of learning were established drew on sources such as Greek equation. Equations in which the highest power of an unknown in many Islamic cities during The Chinese were pioneers and Indian texts (see 250–500), quantity is two are known as quadratic equations (as above), and the Islamic “Golden Age.” in the technology of printing, he is considered to be the those in which the highest power is three are called cubic equations. Perhaps the greatest of these largely due to their invention of inventor of algebra. In his book, was the House of Wisdom paper—possibly as early as the al-Khwarizmi explained the (Bayt al-Hikma), founded in 2nd century BCE—which lent process of balancing both sides Baghdad at the beginning of the itself better to printing than the of an equation (al-jabr in Arabic, papyrus and parchment used hence the modern term algebra), and gave a systematic way of 400 THOUSAND solving quadratic equations, of balancing an equation by as al-Kindi), who in the mid-9th THE NUMBER which had been described transposing terms from one side century wrote a large number of almost 500 years earlier by Greek to the other and canceling out treatises on various scientific OF BOOKS IN mathematician Diophantus of terms that appear on both sides. subjects, ranging from THE HOUSE Alexandria. Central to his mathematics, astronomy, OF WISDOM method was the principle Another prominent scholar at and optics, to medicine and the House of Wisdom was the geography. A scholar of theology AL-KINDI (C.801–873) polymath Abu Yusuf Ya’qub and philosophy, he was also ibn ‘Ishaq al-Kindi (also known responsible for the translation Born and educated in Kufa, near of many classic Greek texts 9th century. As well as housing elsewhere. Developing a form of Baghdad, Al-Kindi was one of and their incorporation into thousands of books, the House woodblock printing on silk that the first major scholars of the Islamic thinking. It is largely of Wisdom encouraged had appeared around 200, they newly founded House of through al-Kindi’s translations research and the translation applied the technique to paper Wisdom. He translated Greek and commentaries on Indian of mathematical, scientific, and used it for the mass scientific and philosophical texts texts that Indian numerals and philosophical texts from production of books. By the into Arabic, and incorporated were introduced to the Islamic ancient Greece. 9th century, it was being used Hellenistic ideas into Islamic world, and subsequently to print promissory notes scholarship. He wrote treatises became the basis for the Persian mathematician and that were in effect a form of on many subjects, including modern system of numbers, astronomer Muhammad ibn Musa paper money issued by the medicine, chemistry, astronomy, although zero was probably al-Khwarizmi (c.780–850) was Chinese government. and mathematics. “discovered” later (see 861–99). one of the most important scholars at the House of Wisdom, Al-Kindi was very sceptical studying both Greek and Indian about alchemy, refuting one scientific treatises. In around of its central ideas—the 820, he described the use of the c.8a1l-o0HfiTWinkhBmiesadaBgoa(hmHydot)auidssefounded c.8de3Cs0ocCAmrailabpl-nceKeudsnhlBadwatialoaigoluraenisnbzbcmrByianoiCgoinokmhoinpsletion 85a5lcdChedhesiimcsngrceuiisobsntveepseotrhwyedoef r c.8p5e0trreAsapl-teiKscaietnnisvddeoic,nwrmyorpeipttdeotiisgccrsina,ep,hy 812 TishsgeuoCevpsehariapnneefmorsreemmnotonfey decs.8c2ri0beAsl-tKhehwasatrriozmlaibe 46

861–99 This statue of Al-Khwarizmi stands The Chinese edition of the Buddhist Diamond Sutra, printed using woodblocks in Khiva, Uzbekistan, his birthplace. on a scroll of paper, is the earliest surviving printed book. transmutation of metals. A CHINESE EDITION OF THE indicates that this was one sealed flask cold water outlet However, alchemy was at the BUDDHIST TEXT, Diamond Sutra, of a number of copies printed root of another discovery—this was discovered in 1907 in for distribution. one liquid cold water time in China. In the early Dunhuang, northwest China. boils into inlet 9th century, Chinese alchemists Although it is probably not the An inscription on a stone were experimenting with various first example of a woodblock in Gwalior, India, dated 876, vapor cooling cooled mixtures of substances to find printed book, it is the earliest contains one of the earliest water jacket vapor the “elixir” of life. One of the known one, and bears the known uses of the symbol mixture of condenses by-products of this quest was date May 11, 868. The text for zero—“0”. Prior to the liquids around into droplets the discovery, in about 855, of and illustrations of Diamond appearance of a specific symbol, heat condenser gunpowder—the first man- Sutra exhibit a great deal of a space was used to indicate source made explosive. It consisted of a sophistication, suggesting that zero, which led to ambiguity and pure liquid mixture of sulfur, carbon (in the the techniques of printing on prevented the development of a DISTILLATION collects form of charcoal), and saltpeter paper were well known in China place value system of numbers in flask (potassium nitrate) – all of which by this time. An inscription at (a system in which the position occur naturally as minerals. The the end of the manuscript of the numeral indicates its mixture’s explosive properties value). The introduction of meant that it was initially used in Distillation is a method of separating the components of a liquid the manufacture of fireworks, a symbol for mixture. The liquid mixture is converted into vapor by heating. As but gunpowder later came to fuel zero in Indian the components of the mixture have different boiling points, they rockets, and was eventually used mathematics vaporize at different rates. The vapor is then cooled so that it in the development of firearms. was a vital step in condenses back into a liquid, which can be collected separately. the development Distillation can be used to extract liquids such as alcohol and of the decimal gasoline, and also to purify liquids, such as salt water. system of notation 10% 15% we use today. This replaced the use of cumbersome the Arabic al kuhl, originally sulfur carbon decimal system Roman numerals. used to describe a powder came to Europe extracted from a mineral, 75% through the Toward the end of the century, but which later came to saltpeter influence of Islamic Arab alchemists developed mean the essence or “spirit” mathematicians, the process of distillation— of a liquid. The apparatus Composition of gunpowder and eventually a method of separating the developed by al-Razi for Sulfur, carbon, and saltpeter, while ingredients of a liquid mixture. distillation has remained quite innocuous individually, become Alchemist Jabir Muhammad ibn Zakariya fundamentally unchanged highly explosive when mixed in the ibn-Hayyan at work al-Razi (c.854–925/35), along to the present day. correct proportions. Alchemy in the Islamic with other alchemists, perfected world involved much the technique and was experimentation, and successful in extracting a form led to the development of alcohol—ethanol or ethyl of many processes alcohol—by distilling wine. that were later used The word alcohol derives from in chemistry. 86sbu8oroTvkhiSv,euitnhtegreaarp,DlriiiiesansmptteirnodinnCtdehdina mathemsay8tmi7ci6baonInlsdfuoiarsnezearo c.8al9c0ohAol-lRfraozmi dwisitniels 47

,,900–930 TRUTH IN MEDICINE IS AN UNATTAINABLE GOAL, AND THE ART AS DESCRIBED IN BOOKS IS FAR BENEATH THE KNOWLEDGE OF AN EXPERIENCED ,,AND THOUGHTFUL PHYSICIAN. Al-Razi, Arab physician, 10th century Arab doctor and chemist al-Razi’s belief in practical experimentation on substances led him to propose an early classification of elements. MUHAMMAD IBN ZAKARIYA dismissed the idea that body melting and extraction. He overlapping plates for mathematics underlying AL-RAZI (Rhazes) was one of temperature is automatically described the distillation of making astronomical the instrument. He the greatest physicians of the raised or lowered when a patient kerosene and petroleum from observations. Although presented formulas in Arab world. Around 900, he drinks warm or cold fluids. His crude oil and gave recipes for al-Fazari was the first spherical trigonometry, wrote Al-Shukuk ala Jalinus clinical practices were advanced preparing hydrochloric and to describe it in the replacing Ptolemy’s (Doubts About Galen), in which he for this time; he ran a psychiatric sulfuric acids. 8th century, al-Battani geometrical criticized Galen’s theory of the ward, and he wrote a treatise worked out the methods. four humors (see 75–250). He attacking untrained physicians. Around 920, Arab astronomer rejected the notion that a balance The Kitab al-Hawi (Comprehensive and mathematician al-Battani of these humors was necessary Book), a collection of his clinical (c.858–929) proffered greater for the health of the patient, and notes, ran to 23 volumes, and insights into the working of contained medical diagnoses, the planispheric astrolabe— AL-RAZI (C.865–925) including the first description a device with a number of of hay fever (or rose-cold). He Born in Rayy, Mesopotamia also wrote a monograph, Kitab map of bodies (now in Iran), al-Razi was a al-Judwar wal Hasba (Treatise on on the celestial physician and philosopher, the Smallpox and Measles), which as well as an alchemist. He was the first work to detail the sphere encouraged experimentation symptoms of smallpox, although as a means of discovery and his explanation—that the disease star pointer his clinical notes became a was caused by the impurities indicates key medieval medical text. He from menstrual blood that stay headed a hospital in Rayy, and in the fetus during pregnancy position of then two in Baghdad. Among and then bubble up to the skin specific star his innovations was the first in later life—betrayed a belief recorded clinical trial—on in sympathetic magic. He was mater, or patients with meningitis. particularly concerned with main section preventing blindness caused by smallpox pustules, and into which advocated regularly bathing latitude the eyes in rose-water. plates slot An alchemist as well as a physician, al-Razi devised a rotating bar classification of elements into spirits and metals and minerals. ecliptic ring He divided the latter into stones, shows path of vitriols, boraces, salts, and other Sun through sky substances, and gave a detailed account of the behavior of each Astrolabe under various processes, such as The user of an astrolabe adjusted its moveable parts to indicate a specific date or time, and the markings on the plates would then indicate the position of the various heavenly bodies. c.9m0Aa0tbahIusle-dlKmKaegamhaarmwltieiicnciaalgirtadienwzermvittehhi’lsoappnaoslw2geerbsra, c.9a1t2reQautisstea oibnnnLuumqbanwersitses 90c0rhi–tu3icm0izoAersl-tRGhaaezloeirnyic c.9tr2e5atAisl-eFoanrambiuwsircittehserapy 9s0ydA0mel–s-p3Rcts0roamimzbiaeslslopfox c.92m0auAtnhl-deBemarltayttaiincngai ldthpiserciaonsvcetirproslelasbe cs.u9r2v7ivaEisnatgrrbolauinesiolsttmrtbodeylaraItbsNeledaasmistuiclus 48