History of energy in Ancient Egypt

Summary: The civilizations of ancient Egypt spanned the period between 3150 b.c.e. and 30 b.c.e. They developed irrigation and agricultural techniques, waterwheels for mining, and forging methods to make tools and weapons. Most of the energy required was provided by muscle power.

One of the ancient names of Egypt is Kemet, literally Black Land, referring to the fertile black mud brought every year by the flooding of the Nile. Ancient Egyptian history spans millennia, which can be divided into a long period of more than 3,000 years, from predynastic times around 3150 b.c.e., when Upper and Lower Egypt were unified for the first time, and the dynastic period that ended in 30 b.c.e., when Egypt became a Roman province.

Monumental pyramids, temples, and obelisks testify to Egypt’s advanced capabilities in quarrying, surveying, and construction techniques. Furthermore, ancient Egyptians developed a system of mathematics, used irrigation systems and agricultural production techniques, built the first known ships, took advantage of an effective system of medicine, and were famous for their faience and glass technologies. Besides being technologically advanced, the ancient Egyptians were very artistic. They developed writing and new forms of literature, such as love poetry and coffin texts, written in dramatic form and used in rituals. Today there are many existing paintings, reliefs, and sculptures attesting Egypt’s lasting cultural legacy. Besides being an imperial power and engaging in strategic military actions, Egypt also produced the earliest known peace treaty.

Agriculture and Irrigation

Farming in Egypt was dependent on the cycle of the Nile River. Its annual flooding, from June to September, brought water and fertile silt onto the surrounding land and was the precondition for the region’s agriculture. It also prompted the names of the three distinct seasons during a 365-day calendar: Akhet (flooding), Peret (planting), and Shemu (harvesting). Since Egypt received little rainfall, fields were irrigated by the use of ditches. Before sowing, the farmers had to remove silt from the ditches, basins, and sluices, then plow the soil. Plows were pulled by men or oxen. From October to February, donkeys and oxen were used to trample seed into the soil.

From March to May, farmers harvested their crops, mainly emmer, barley, and flax, using sickles. They also harvested vegetables, other cereal grains, and vines. Women and children had to help during the harvest season. The grain was threshed with a flail or stomped out by oxen. Camels were not used as beasts of burden until the Late Period. After winnowing, the grain was ground into flour, brewed into beer, or stored for later use. Additionally, the farmers used nets and harpoons for fishing. Estates were owned by the pharaoh, temples, and liege lords. Taxes were determined on the basis of the flood level and the estimated harvest.

In predynastic times, farmers used only natural, semiannual basins. Later, artificial half-yearly and year-round basins were invented, supplying water for irrigation. During the 18th Dynasty (1550–1295 b.c.e.) the shaduf (or shadoof), a simple water pump, was introduced. Two vertical stakes supported a third, horizontal stake, which acted as a lever. At one end was a pot, and at the other end was a counterweight. The shaduf could be handled by one person. Later, in the 5th century b.c.e., the shaduf was replaced by more effective lifting equipment, such as a version of Archimedes’s screw named the tanhur.

During the Ptolemaic Dynasty, the waterwheel was invented, leading to the construction of water scoops. Called sakijes, these multiple clay vases were mounted on the wheel to scoop water, lifting it to higher elevations, where the water was poured into gutters that emptied onto fields. The sakijes were powered by camels, oxen, or donkeys.

The Nile River has always been of critical economic importance, and its levels of flooding have therefore been measured by officials for more than 5,000 years and have been written down for more than 13 centuries. The levels were classified into 13 cubits (the length of a man’s forearm, approximately 18 inches), which signaled that the harvest would be insufficient and lead to hunger; 14 cubits, signifying sufficiency; 15 cubits, signifying satisfaction; 16 cubits, signifying happiness; 17 cubits, signifying abundance; 18 cubits, signifying danger; and 19 cubits, signifying destruction.

To gauge the water level, Sesostris I (who ruled 1971–26 b.c.e.) constructed a water measurement device, called a nilometer (literally, “Nile measure”). It became widely used either as a built structure or cut into rock. The oldest of these devices have been found at Fort Semne on the island Elephantine close to Aswan and on the island of Roda near Cairo. During the Late Period, the Big Canal was built, which would convey excess water during flooding in order to prevent damage to fields and houses. The water flow was controlled by means of sluices, so that it could flow back through the Big Canal into the Nile during dry months and prevent drought in the northern districts.

Shipbuilding

The very first boats were made of reed bunches. As early as 3,000 b.c.e., ancient Egyptians knew how to build ships of wooden planks. They used tree nails and even mortise and tenon joints to fasten the planks together and then caulked the seams with pitch. At the time, strategic amphibious warfare, used first against Nubian villages, was developing. Satches and sekhets, which were 13- to 20- foot (21- to 32-meter) longboats, were used during the Old Kingdom, sailing for transport purposes on the Nile. Although constructing large boats and sailing on the Nile, the ancient Egyptians did not engage in sailing or shipping in the Mediterranean or Red Sea. During the next dynasties, the Egyptians did not develop further innovations in shipbuilding but relied on technological advancements of other nations, resulting in a dangerous dependency.

Under Rameses II (who reigned 1279–13 b.c.e.) and Rameses III (reigned 1186 or 1187 to 1155 or 1156 b.c.e.), the menesh, a type of ship built in Phoenicia, was widely used. So-called byblos boats, used for sailing on the sea, originated in Syria-Palestine. During the Intermediate Period, the navy was an important military branch, manned with mercenaries. Commanders were subordinated directly to the pharaoh. About 2450 b.c.e., merchant ships were used for the first time to transport troops, about 200 men per ship, to Palestine.

The ships’ size of about 30 meters in length stayed unaltered, although certain construction and rigging features changed. During the 18th Dynasty, Egypt had its own marine corps. The higher ranks were composed of the elite middle class. At that time, the navy was able to perform complicated naval maneuvers, such as during Kamose’s campaign against the Hyksos in the harbor of Avaris (ca. 1555–50 b.c.e.).

To protect Egyptian borders against potential enemies and to maintain the pharaoh’s trade monopoly, several fortresses along the Nile River and the Mediterranean coast were built.

Weapons and the Military

Since the times of the Old Kingdom (2707–2216 b.c.e.), the military organization and logistics were well developed, supported by scribes and a centralized administration. Military hierarchy developed in the Middle Kingdom (2055–1650 b.c.e.). By the New Kingdom (1550–69 b.c.e.), the Egyptian military was organized in three major branches, infantry, chariotry, and navy, as well as additional divisions stationed in garrisons and foreign mercenaries. At the time, the army consisted of four divisions of 5,000 soldiers each. Further structure included the brigade (pa-djetu) of 500 to 1,000 soldiers, which formed two regiments (sa-u). One regiment was divided into four or five companies, distinguished by the kinds of weapons they used—for example, bowmen or spearmen.

Weapons in ancient Egypt varied by military units and included battleaxes, khopesh swords (adopted from Asiatic soldiers), bows and arrows, spears, and slingshots. Maces, daggers, and battle-axes with copper blades were the most effective weapons in hand-to-hand fights. With the New Kingdom, copper was replaced by bronze in blades and projectile weapons. In early times, soldiers used shields made of dried animal skins to protect themselves. Later they changed to wooden shields studded with bronze. Simple arrows were made of reeds, fletched with three feathers and tipped with flint or hardwood and later, during the New Kingdom, tipped with bronze.

Originally, the throw stick and the spear were used for hunting rather than for military purposes. During the Old and Middle Kingdoms of Egypt’s dynastic period, the spear consisted of a wooden shaft about the height of a man, and a pointed blade made of copper or flint. Rameses III was depicted killing a Libyan with a spear.

Besides weapons, the ancient Egyptian military was led by professional officer corps and used trained recon units with an advanced communication system, including drummers, trumpets, runners (pa-hereru), and messengers on horses.

With the Middle Kingdom, ancient Egyptian medicine advanced. Many battlefield injuries could be treated: bone fractures, gashes, bruises, and amputations. Doctors knew how to use splints, clean and suture wounds, stanch blood, set bandages, and take advantage of opium as an analgesic. Nonetheless, there was no military sanitary service. Doctors worked in the temples.

During the New Kingdom, the composite bow came into use. Its draw weight was dramatically greater than that of a simple wooden bow. Therefore, horn was added to the arch of the bow to support the wood so the bow could withstand the tension of the draw. All layers were glued together and covered with birch bark. The composite bow was introduced by the Asiatic Hyksos, along with other advanced technologies originating in Mesopotamia, such as chariots, helmets, and bronze armor. While in other countries chariots were exclusively reserved for noblemen, in Egypt they belonged to the common military equipment but formed an elite unit (pa-djetu), contributing immense mobility and speed on the battlefield. Chariots (weweret) were handled by a driver (kedjen) and a fighter (seneni) who usually was an archer.

During the 26th Dynasty, long spears and lances became the major weapons. After eviction of the Hyksos, the pharaohs used the adopted technologies to focus on expansionist power politics toward Nubia, Syria, and Palestine. At the time of the New Kingdom, the population of Palestine numbered about 140,000 inhabitants, while Egypt had 2.9 million inhabitants. During their invasions, the Egyptians carried disassembled boats with them, applying an amphibian strategy at the Nile and the Euphrates Rivers.

After 3,000 years of military development and implementation of 34 military disctricts, the troops were organized into a national army, based on professional soldiers and conscripts, recruiting one in 10 from the general public. Conscription was enforced already during the Old Kingdom, but with a recruiting factor of one in 100 of all male inhabitants. Additionally, mercenaries from Nubia, Kush, and Libya were hired to fight for Egypt. The vizier served as secretary of war. During peacetime, soldiers and mercenaries had to work in quarries and mines, transport building materials, build structures, protect trade routes and Egyptian borders, and repress civil wars.

At no time were towns fortified, but watchtowers were installed at strategic points, and temples, with their high surrounding walls, served as refuges.

Architecture

Egypt is rich in building resources, such as granite and metal ores. There were abundant mines of copper and lead ores, gypsum, and semiprecious stones, such as alabaster and carnelian. Ptolemy and the Romans admired Egypt’s emeralds and amethysts, to be found in the desert. In Nubia, for a long time an Egyptian territory, there was gold; the lack of this resource was deeply felt when Nubia was lost to the empire. One of the first maps known is of a gold mine in Nubia. Lead was used to make net sinkers and plumb bobs. Early tools were made of flint. Starting in 4500 b.c.e., the ancient Egyptians mined copper, mainly as malachite ore in the Sinai, sometimes in 328-foot (100-meter-deep) tunnels. Copper became the main material for toolmaking, which is remarkable, because its high melting point required advanced technology to reach the required temperature. With the New Kingdom, iron became more common, which led, among other things, to the decline of Egypt: The country was no longer economically independent, but dependent on imports from other nations.

From predynastic periods until the Second Dynasty, adobes were used for building. In the Third Dynasty, construction material changed from clay to stone and reached a climax of achievements during the Fourth Dynasty. Stone quarries—providing limestone, granite, basalt, and sandstone—existed since at least 2700 b.c.e., when the first structures of stone were built.

The famous Egyptian pyramids emanated from so-called mastabas. A mastaba is a bench-shaped structure that covered the grave of a distinguished personality. Mastabas were common until the time of the Middle Kingdom, often mantled with greywacke, including a sanctuary and a pseudo-door at the west side. The first big structure using stone as main material was the step pyramid of the pharaoh Djoser, built by Imhotep. This was an amazing technological achievement in the handling of huge volumes of stone. All the structural elements were assembled without mortar. Aesthetically, these early stone buildings imitated former palaces, copying the shape of wood structures and reed bunch pillars. From then on, pyramids were often covered with Tura limestone.

Under the reign of Snefru (or Snofru), during the Fourth Dynasty, the engineering of stone buildings reached a peak. Technological feats included the transportation of the huge granite cuboids to the center of the pyramid and of the sarcophagus to the grave chamber, as well as the interlocking system of precisely cut fall stones. The Egyptians’ method of precise quarrying is not completely understood today. Later pyramids were based on a stone framework, filled with boulders and adobe, and covered with limestone. During Roman times, these pyramids became limestone quarries, resulting in the pyramids’ destruction from the erosion of wind and rain. Cheops, a son of Snefru, built the Cheops pyramid, which is known today as one of the wonders of the world. Although 7.5 million cubic feet (2.34 million cubic meters) of stone were stacked in 210 layers, about 475 feet (145 meters) high, this pyramid shows impressive accuracy regarding the length of the edges, their angles, and the leveling. The Cheops pyramid is part of a necropolis on an area of more than 100 hectares. Aswan, where granite was quarried, and Giza, where the famous Cheops pyramid was built, are 420 miles apart, demonstrating the impressive logistical skills of the ancient Egyptians.

During the Fifth Dynasty, the first extensive burial sites were built. They consisted of the valley temple, alley, funerary temple, and pyramid. Around such sites, graves of important officials can be found.

Later, during the 18th Dynasty, the first dynasty of the New Kingdom, famous temple sites were built. Examples include the temples of Rameses II, Amenhotep (or Amenhophis) III, and the Temple of Hatshepsut—all located in the Valley of the Kings on the west bank of the Nile, opposite to Thebes (modern Luxor). Sometimes a holy lake or a house of life—a kind of a training center for artists and physicians—can be found next to a temple.

Some unanswered questions remain about how the ancient Egyptians could transport such giant stones in such great volumes and compile such precisely measured structures, given all their logistical and technological challenges. At least some information comes down to us through depictions inside the pyramids and in a report by Herodotus, a Greek historian, who visited Egypt around 450 b.c.e. Herodotus describes the quarrying and shipping of the stones from the Arabic mountains over the Nile River to the Libyan Desert, as well as construction of roads for the same purpose, done by 10,000 forced laborers. Although such drudgery was forbidden after 1889 b.c.e., the regulations were repeatedly dodged. It is assumed that the flooding season was used for shipping, because then high water levels in the Nile River Delta reached almost to the desert, thus dramatically reducing the distances between ships and construction sites.

Herodotus also writes about wooden scaffoldings used to lift the heavy stones from one step of the pyramid to the next, suggesting that pyramids were always step pyramids first and attained their final flat surface later, through covering and planing. An alternative theory posits that ramps rather than wooden scaffolds could have been used to bring stones to the tops of the pyramids, first pulled by men and later by oxen.

Herodotus’s report contains a passage about a water canal built into the grave chamber. Today it is generally understood that he wrote about canals that were dug around the construction site and filled with groundwater for leveling purposes.

Numbers and Mathematics

Written evidence of the knowledge of mathematics dates back to at least 3000 b.c.e., with the ivory labels found at Abydos. Also, in depictions of offering scenes, numerals are given to indicate the number of items offered—for instance, the Narmer macehead records offerings of 400,000 oxen, 1,422,000 goats, and 120,000 prisoners. In another case, a princess is shown with offerings of 1,000 oxen, bread, and beer.

The system of ancient Egyptian numerals was a decimal system, used until the early 1st millennium c.e. The number 1 was represented by a simple stroke, the number 2 by two stokes, and so on. The numbers 10, 100, 1,000, 10,000, and 1,000,000 had their own hieroglyphs. There was no known sign for zero. The Egyptian number system was, like later Roman numerals, additive. Large numbers were composed by adding the individual numbers, respectively glyphs, together. Besides addition and subtraction, the Egyptians understood unit fractions, typically fractions of the form 1/n, and equations with one variable.

The most important, earliest documents illuminating the mathematical skills of the ancient Egyptians date to the 12th Dynasty (1990–1800 b.c.e.). These documents include the Moscow Mathematical Papyrus, Rhind Mathematical Papyrus, the Egyptian Mathematical Leather Roll, the Lahun Mathematical Papyri (which are a part of the large collection of Kahun Papyri), and the Berlin Papyrus. They are mathemical problem texts, including both algebra and geometry problems, given with solutions, including tables and practical computing examples. The Egyptian Mathematical Leather Roll, for instance, is a table of unit fractions that are expressed as sums of other unit fractions. The Rhind Mathematical Papyrus and some of the other texts contain 2/n tables. The mathematical problems include simple fraction expressions, followed by completion (sekhet) problems and more involved linear equations (aha problems). The sekhet problems indicate an understanding of the idea of geometric similarity, used to compute the slopes of pyramids. The use of the Horus eye fractions shows some rudimentary knowledge of geometric progression. Further division and squaring were known, and Egyptian multiplication was reduced to repeated addition of the number to be multiplied.

Later documents include the literary Papyrus Anastasi I, written during the New Kingdom, and the Papyrus Wilbour from the time of Rameses III, which recorded land measurements. Because of the annual cyclical flooding of the Nile and the ensuing destruction of field borders, the ancient Egyptians developed planimetric computations of areas of several geometric shapes to avoid conflicts over land occupancy.

Regarding the construction of the pyramids, the ancient Egyptians learned how to compute the area, the shell, and the volume of a square pyramid using the equation V = G × h/3, where G = (a² + ab + b²). They were also able to compute the volumes of cylinders, cones, and spheres by means of 16/9, an approximation of pi (p), and a precise right angle using some Pythagorean triples. Furthermore, it is generally agreed that already in ancient Egypt the golden ratio was known and used for harmonious design of buildings.

Faience and Glass

Already in the predynastic period, the ancient Egyptians had developed a glassy material known as faience, a nonclay ceramic made of silica, lime, and soda, to which was added a colorant, commonly a copper salt. The material was used as a type of artificial semiprecious stone for making beads, tiles, figurines, and small wares.

The ancient Egyptians were also very skilled in manufacturing glass objects of diverse colors, such as yellow, red, green, blue, purple, and white, and the glass could be made either transparent or opaque.

Bibliography

Chace, Arnold Buffum. The Rhind Mathematical Papyrus: Free Translation and Commentary With Selected Photographs, Translations, Transliterations and Literal Translations. 2 vols. Classics in Mathematics Education 8. Oberlin, OH: Mathematical Association of America, 1927–29.

Clagett, Marshall. Ancient Egyptian Science: A Source Book. Vol. 3, Ancient Egyptian Mathematics. Memoirs of the American Philosophical Society 232. Philadelphia: American Philosophical Society, 1999.

Gillings, Richard J. Mathematics in the Time of the Pharaohs. Cambridge, MA: MIT Press, 1972.

Robins, R. Gay, and Charles C. D. Shute. The Rhind Mathematical Papyrus: An Ancient Egyptian Text. London: British Museum Publications, 1987.

Strudwick, Nigel G., and Ronald J. Leprohon. Texts From the Pyramid Age. Boston: Brill Academic, 2005.