8. Science
Origins of Egyptian science—Mathematics—Astronomy and the calendar—Anatomy and physiology—Medicine, surgery and hygiene
The scholars of Egypt were mostly priests, enjoying, far from the turmoil of life, the comfort and security of the temples; and it was these priests who, despite all their superstitions, laid the foundations of Egyptian science. According to their own legends the sciences had been invented some 18,000 B.C. by Thoth, the Egyptian god of wisdom, during his three-thousand-year-long reign on earth; and the most ancient books in each science were among the twenty thousand volumes composed by this learned deity.*161Our knowledge does not permit us to improve substantially upon this theory of the origins of science in Egypt.
At the very outset of recorded Egyptian history we find mathematics highly developed; the design and construction of the Pyramids involved a precision of measurement impossible without considerable mathematical lore. The dependence of Egyptian life upon the fluctuations of the Nile led to careful records and calculations of the rise and recession of the river; surveyors and scribes were continually remeasuring the land whose boundaries had been obliterated by the inundation, and this measuring of the land was evidently the origin of geometry.163 Nearly all the ancients agreed in ascribing the invention of this science to the Egyptians.164 Josephus, however, thought that Abraham had brought arithmetic from Chaldea (i.e., Mesopotamia) to Egypt;165 and it is not impossible that this and other arts came to Egypt from “Ur of the Chaldees,” or some other center of western Asia.
The figures used were cumbersome—one stroke for 1, two strokes for 2, . . . nine strokes for 9, with a new sign for 10. Two 10 signs stood for 20, three 10 signs for 30, . . . nine for 90, with a new sign for 100. Two 100 signs stood for 200, three 100 signs for 300, . . . nine for 900, with a new sign for 1000. The sign for 1,000,000 was a picture of a man striking his hands above his head, as if to express amazement that such a number should exist.166 The Egyptians fell just short of the decimal system; they had no zero, and never reached the idea of expressing all numbers with ten digits: e.g., they used twenty-seven signs to write 999.167 They had fractions, but always with the numerator 1; to express ¾ they wrote ½ + ¼. Multiplication and division tables are as old as the Pyramids. The oldest mathematical treatise known is the Ahmes Papyrus, dating back to 2000-1700 B.C.; but this in turn refers to mathematical writings five hundred years more ancient than itself. It illustrates by examples the computation of the capacity of a barn or the area of a field, and passes to algebraic equations of the first degree.168 Egyptian geometry measured not only the area of squares, circles and cubes, but also the cubic content of cylinders and spheres; and it arrived at 3.16 as the value of π.169 We enjoy the honor of having advanced from 3.16 to 3.1416 in four thousand years.
Of Egyptian physics and chemistry we know nothing, and almost as little of Egyptian astronomy. The star-gazers of the temples seem to have conceived the earth as a rectangular box, with mountains at the corners upholding the sky.170 They made no note of eclipses, and were in general less advanced than their Mesopotamian contemporaries. Nevertheless they knew enough to predict the day on which the Nile would rise, and to orient their temples toward that point on the horizon where the sun would appear on the morning of the summer solstice.171 Perhaps they knew more than they cared to publish among a people whose superstitions were so precious to their rulers; the priests regarded their astronomical studies as an esoteric and mysterious science, which they were reluctant to disclose to the common world.172 For century after century they kept track of the position and movements of the planets, until their records stretched back for thousands of years. They distinguished between planets and fixed stars, noted in their catalogues stars of the fifth magnitude (practically invisible to the unaided eye), and charted what they thought were the astral influences of the heavens on the fortunes of men. From these observations they built the calendar which was to be another of Egypt’s greatest gifts to mankind.
They began by dividing the year into three seasons of four months each: first, the rise, overflow and recession of the Nile; second, the period of cultivation; and third, the period of harvesting. To each of these months they assigned thirty days, as being the most convenient approximation to the lunar month of twenty-nine and a half days; their word for month, like ours, was derived from their symbol for the moon.* At the end of the twelfth month they added five days to bring the year into harmony with the river and the sun.174 As the beginning of their year they chose the day on which the Nile usually reached its height, and on which, originally, the great star Sirius (which they called Sothis) rose simultaneously with the sun. Since their calendar allowed only 365, instead of 365¼ days to a year, this “heliacal rising” of Sirius (i.e., its appearance just before sunrise, after having been invisible for a number of days) came a day later every four years; and in this way the Egyptian calendar diverged by six hours annually from the actual calendar of the sky. The Egyptians never corrected this error. Many years later (46 B.C.) the Greek astronomers of Alexandria, by direction of Julius Caesar, improved this calendar by adding an extra day every fourth year; this was the “Julian Calendar.” Under Pope Gregory XIII (1582) a more accurate correction was made by omitting this extra day (February 29th) in century years not divisible by 400; this is the “Gregorian Calendar” that we use today. Our calendar is essentially the creation of the ancient Near East.†175
Despite the opportunities offered by embalming, the Egyptians made relatively poor progress in the study of the human body. They thought that the blood-vessels carried air, water, and excretory fluids, and they believed the heart and bowels to be the seat of the mind; perhaps if we knew what they meant by these terms we should find them not so divergent from our own ephemeral certainties. They described with general accuracy the larger bones and viscera, and recognized the function of the heart as the driving power of the organism and the center of the circulatory system: “its vessels,” says the Ebers Papyrus,176 “lead to all the members; whether the doctor lays his finger on the forehead, on the back of the head, on the hands, . . . or on the feet, everywhere he meets with the heart.” From this to Leonardo and Harvey was but a step—which took three thousand years.
The glory of Egyptian science was medicine. Like almost everything else in the cultural life of Egypt, it began with the priests, and dripped with evidences of its magical origins. Among the people amulets were more popular than pills as preventive or curative of disease; disease was to them a possession by devils, and was to be treated with incantations. A cold for instance, could be exorcised by such magic words as: “Depart, cold, son of a cold, thou who breakest the bones, destroyest the skull, makest ill the seven openings of the head! . . . Go out on the floor, stink, stink, stink!”177—a cure probably as effective as contemporary remedies for this ancient disease. From such depths we rise in Egypt to great physicians, surgeons and specialists, who acknowledged an ethical code that passed down into the famous Hippocratic oath.178 Some of them specialized in obstetrics or gynecology, some treated only gastric disorders, some were oculists so internationally famous that Cyrus sent for one of them to come to Persia.179 The general practitioner was left to gather the crumbs and heal the poor; in addition to which he was expected to provide cosmetics, hair-dyes, skin-culture, limb-beautification, and flea-exterminators.180
Several papyri devoted to medicine have come down to us. The most valuable of them, named from the Edwin Smith who discovered it, is a roll fifteen feet long, dating about 1600 B.C., and going back for its sources to much earlier works; even in its extant form it is the oldest scientific document known to history. It describes forty-eight cases in clinical surgery, from cranial fractures to injuries of the spine. Each case is treated in logical order, under the heads of provisional diagnosis, examination, semeiology, diagnosis, prognosis, treatment, and glosses on the terms used. The author notes, with a clarity unrivaled till the eighteenth century of our era, that control of the lower limbs is localized in the “brain”—a word which here appears for the first time in literature.181
The Egyptians enjoyed a great variety of diseases, though they had to die of them without knowing their Greek names. The mummies and papyri tell of spinal tuberculosis, arteriosclerosis, gall-stones, small-pox, infantile paralysis, anemia, rheumatic arthritis, epilepsy, gout, mastoiditis, appendicitis, and such marvelous affections as spondylitis deformans and achondroplasia. There are no signs of syphilis or cancer; but pyorrhea and dental caries, absent in the oldest mummies, become frequent in the later ones, indicating the progress of civilization. The atrophy and fusion of the bones of the small toe, often ascribed to the modern shoe, was common in ancient Egypt, where nearly all ages and ranks went barefoot.182
Against these diseases the Egyptian doctors were armed with an abundant pharmacopoeia. The Ebers Papyrus lists seven hundred remedies for everything from snake-bite to puerperal fever. The Kahun Papyrus (ca. 1850 B.C.) prescribes suppositories apparently used for contraception.182aThe tomb of an Eleventh Dynasty queen revealed a medicine chest containing vases, spoons, dried drugs, and roots. Prescriptions hovered between medicine and magic, and relied for their effectiveness in great part on the repulsiveness of the concoction. Lizard’s blood, swine’s ears and teeth, putrid meat and fat, a tortoise’s brains, an old book boiled in oil, the milk of a lying-in woman, the water of a chaste woman, the excreta of men, donkeys, dogs, lions, cats and lice—all these are found in the prescriptions. Baldness was treated by rubbing the head with animal fat. Some of these cures passed from the Egyptians to the Greeks, from the Greeks to the Romans, and from the Romans to us; we still swallow trustfully the strange mixtures that were brewed four thousand years ago on the banks of the Nile.183
The Egyptians tried to promote health by public sanitation,* by circumcision of males,†185 and by teaching the people the frequent use of the enema. Diodorus Siculus187 tells us:
In order to prevent sicknesses they look after the health of their body by means of drenches, fastings and emetics, sometimes every day, and sometimes at intervals of three or four days. For they say that the larger part of the food taken into the body is superfluous, and that it is from this superfluous part that diseases are engendered.‡
Pliny believed that this habit of taking enemas was learned by the Egyptians from observing the ibis, a bird that counteracts the constipating character of its food by using its long bill as a rectal syringe.188 Herodotus reports that the Egyptians “purge themselves every month, three days successively, seeking to preserve health by emetics and enemas; for they suppose that all diseases to which men are subject proceed from the food they use.” And this first historian of civilization ranks the Egyptians as, “next to the Libyans, the healthiest people in the world.189