Editing Ancient Egypt (section)

==Technology, medicine and mathematics==
<!-- This section is linked from [[Civilization]] -->

===Technology===
{{Main|Ancient Egyptian technology}}
[[File:Egyptian glass jar.jpg|thumb|right|Glassmaking was a highly developed art.]]

In technology, medicine, and mathematics, ancient Egypt achieved a relatively high standard of productivity and sophistication. Traditional [[empiricism]], as evidenced by the [[Edwin Smith Papyrus|Edwin Smith]] and [[Ebers Papyrus|Ebers papyri]] ({{circa|1600 BC}}), is first credited to Egypt. The Egyptians created their own alphabet and [[decimal|decimal system]].

===Faience and glass===
Even before the Old Kingdom, the ancient Egyptians had developed a glassy material known as [[Egyptian faience|faience]], which they treated as a type of artificial semi-precious stone. Faience is a non-clay ceramic made of [[Silicon dioxide|silica]], small amounts of [[Calcium oxide|lime]] and [[Sodium oxide|soda]], and a colorant, typically copper.{{sfnp|Nicholson|Shaw|2000|p=177}} The material was used to make beads, tiles, figurines, and small wares. Several methods can be used to create faience, but typically production involved application of the powdered materials in the form of a paste over a clay core, which was then fired. By a related technique, the ancient Egyptians produced a pigment known as [[Egyptian blue]], also called blue frit, which is produced by fusing (or [[sintering]]) silica, copper, lime, and an alkali such as natron. The product can be ground up and used as a pigment.{{sfnp|Nicholson|Shaw|2000|p=109}}

The ancient Egyptians could fabricate a wide variety of objects from glass with great skill, but it is not clear whether they developed the process independently.{{sfnp|Nicholson|Shaw|2000|p=195}} It is also unclear whether they made their own raw glass or merely imported pre-made ingots, which they melted and finished. However, they did have technical expertise in making objects, as well as adding [[Micromineral|trace elements]] to control the color of the finished glass. A range of colors could be produced, including yellow, red, green, blue, purple, and white, and the glass could be made either transparent or opaque.{{sfnp|Nicholson|Shaw|2000|p=215}}

===Medicine===
{{Main|Ancient Egyptian medicine}}
The medical problems of the ancient Egyptians stemmed directly from their environment. Living and working close to the Nile brought hazards from [[malaria]] and debilitating [[schistosomiasis]] parasites, which caused liver and intestinal damage. Dangerous wildlife such as crocodiles and hippos were also a common threat. The lifelong labors of farming and building put stress on the spine and joints, and traumatic injuries from construction and warfare all took a significant toll on the body. The grit and sand from stone-ground flour abraded teeth, leaving them susceptible to [[abscess]]es (though [[dental caries|caries]] were rare).{{sfnp|Filer|1995|p=94}}

The diets of the wealthy were rich in sugars, which promoted [[Periodontitis|periodontal disease]].{{sfnp|Filer|1995|pp=78–80}} Despite the flattering physiques portrayed on tomb walls, the overweight mummies of many of the upper class show the effects of a life of overindulgence.{{sfnp|Filer|1995|p=21}} Adult [[life expectancy]] was about 35 for men and 30 for women, but reaching adulthood was difficult as about one-third of the population died in infancy.{{efn|Figures are given for ''adult'' life expectancy and do not reflect life expectancy ''at birth.'' ({{harvp|Filer|1995|p=25}})}}

[[File:Edwin Smith Papyrus v2.jpg|thumb|left|The [[Edwin Smith Papyrus|Edwin Smith surgical papyrus]] describes anatomy and medical treatments, written in [[hieratic]], {{circa|1550 BC}}.]]
Ancient Egyptian physicians were renowned in the ancient Near East for their healing skills, and some, such as [[Imhotep]], remained famous long after their deaths.{{sfnp|Filer|1995|p=39}} Herodotus remarked that there was a high degree of specialization among Egyptian physicians, with some treating only the head or the stomach, while others were eye-doctors and dentists.{{sfnp|Strouhal|1989|p=243}} Training of physicians took place at the ''Per Ankh'' or "House of Life" institution, most notably those headquartered in [[Bubastis|Per-Bastet]] during the New Kingdom and at [[Abydos, Egypt|Abydos]] and [[Sais, Egypt|Saïs]] in the Late period. [[Medical papyri]] show [[Empirical evidence|empirical knowledge]] of anatomy, injuries, and practical treatments.{{sfnp|Strouhal|1989|pp=244–246}}

Wounds were treated by bandaging with raw meat, white linen, sutures, nets, pads, and swabs soaked with honey to prevent infection,{{sfnp|Strouhal|1989|p=250}} while [[opium]], [[thyme]], and [[Atropa belladonna|belladona]] were used to relieve pain. The earliest records of burn treatment describe burn dressings that use the milk from mothers of male babies. Prayers were made to the goddess [[Isis]]. Moldy bread, honey, and copper salts were also used to prevent infection from dirt in burns.{{sfnp|Pećanac|Janjić|Komarcević|Pajić|2013|pages=263–267}} Garlic and onions were used regularly to promote good health and were thought to relieve [[asthma]] symptoms. Ancient Egyptian surgeons stitched wounds, set [[broken bones]], and amputated diseased limbs, but they recognized that some injuries were so serious that they could only make the patient comfortable until death occurred.{{sfnp|Filer|1995|p=38}}

===Maritime technology===
Early Egyptians knew how to assemble planks of wood into a [[hull (watercraft)|ship hull]] and had mastered advanced forms of [[shipbuilding]] as early as 3000{{nbsp}}BC. The [[Archaeological Institute of America]] reports that the oldest [[Plank (wood)|planked]] [[ship]]s known are the [[Abydos boats]].{{sfnp|Ward|2001}} A group of 14 discovered ships in [[Abydos, Egypt|Abydos]] were constructed of wooden planks "sewn" together. Discovered by Egyptologist David O'Connor of [[New York University]],{{sfnp|Schuster|2000}} woven [[strap]]s were found to have been used to lash the planks together,{{sfnp|Ward|2001}} and [[Cyperus papyrus|reeds]] or [[Poaceae|grass]] stuffed between the planks helped to seal the seams.{{sfnp|Ward|2001}} Because the ships are all buried together and near a mortuary belonging to [[Khasekhemwy|Pharaoh Khasekhemwy]], originally they were all thought to have belonged to him, but one of the 14 ships dates to 3000{{nbsp}}BC, and the associated pottery jars buried with the vessels also suggest earlier dating. The ship dating to 3000{{nbsp}}BC was {{convert|75|ft|m}} long and is now thought to perhaps have belonged to an earlier pharaoh, perhaps one as early as [[Hor-Aha]].{{sfnp|Schuster|2000}}

Early Egyptians also knew how to assemble planks of wood with [[treenail]]s to fasten them together, using [[Pitch (resin)|pitch]] for [[caulking]] the seams. The "[[Khufu ship]]", a {{convert|43.6|m|ft|adj=on}} vessel sealed into a pit in the Giza pyramid complex at the foot of the [[Great Pyramid of Giza]] in the [[Fourth dynasty of Egypt|Fourth Dynasty]] around 2500{{nbsp}}BC, is a full-size surviving example that may have filled the symbolic function of a [[solar barque]]. Early Egyptians also knew how to fasten the planks of this ship together with [[mortise and tenon]] joints.{{sfnp|Ward|2001}}

[[File:Ancient Egyptian Seafaring Ship.jpg|thumb|left|Seagoing ship of an expedition to Punt, from a relief of [[Mortuary temple of Hatshepsut|Hatshepsut's Mortuary temple]], Deir el-Bahari]]Large seagoing ships are known to have been heavily used by the Egyptians in their trade with the city states of the eastern Mediterranean, especially [[Byblos]] (on the coast of modern-day Lebanon), and in several expeditions down the Red Sea to the [[Land of Punt]]. In fact one of the earliest Egyptian words for a seagoing ship is a "Byblos Ship", which originally defined a class of Egyptian seagoing ships used on the Byblos run; however, by the end of the Old Kingdom, the term had come to include large seagoing ships, whatever their destination.{{sfnp|Wachsmann|2009|p=19}}

In 1977, an ancient north–south canal was discovered extending from [[Lake Timsah]] to the Ballah Lakes.{{sfnp|Shea|1977|pp=31–38}} It was dated to the [[Middle Kingdom of Egypt]] by extrapolating dates of ancient sites constructed along its course.{{sfnp|Shea|1977|pp=31–38}}{{efn|See [[Suez Canal]].}}

In 2011, archaeologists from Italy, the United States, and Egypt, excavating a dried-up lagoon known as [[Mersa Gawasis]], unearthed traces of an ancient harbor that once launched early voyages, such as [[Hatshepsut]]'s Punt, expedition onto the open ocean. Some of the site's most evocative evidence for the ancient Egyptians' seafaring prowess include large ship timbers and hundreds of feet of ropes, made from papyrus, coiled in huge bundles.{{sfnp|Curry|2011}} In 2013, a team of Franco-Egyptian archaeologists discovered what is believed to be the world's oldest port, dating back about 4500 years, from the time of King Khufu, on the Red Sea coast, near Wadi el-Jarf (about 110 miles south of [[Suez]]).{{sfnmp|1a1=Boyle|1y=2013|2a1=Lorenzi|2y=2013}}

===Mathematics===
{{Main|Ancient Egyptian mathematics}}
[[File:Senenmut-Grab.JPG|right|thumb|Facsimile of the [[Astronomical ceiling of Senenmut's Tomb|Astronomical chart in Senemut's tomb]], 18th dynasty{{sfnp|Astronomical Ceiling|2020}}]]

The earliest attested examples of mathematical calculations date to the predynastic [[Naqada]] period, and show a fully developed [[Egyptian numerals|numeral system]].{{efn|Understanding of Egyptian mathematics is incomplete due to paucity of available material and lack of exhaustive study of the texts that have been uncovered ({{harvp|Imhausen|2007|p=13}}).}} The importance of mathematics to an educated Egyptian is suggested by a New Kingdom fictional letter in which the writer proposes a scholarly competition between himself and another scribe regarding everyday calculation tasks such as accounting of land, labor, and grain.{{sfnp|Imhausen|2007|p=11}} Texts such as the [[Rhind Mathematical Papyrus]] and the [[Moscow Mathematical Papyrus]] show that the ancient Egyptians could perform the four basic mathematical operations—addition, subtraction, [[Ancient Egyptian multiplication|multiplication]], and division—use fractions, calculate the areas of rectangles, triangles, and circles and compute the volumes of boxes, columns and pyramids. They understood basic concepts of [[Egyptian algebra|algebra]] and [[Egyptian geometry|geometry]], and could solve [[systems of equations]].{{sfnp|Clarke|Engelbach|1990|p=222}}

{{hiero | {{frac|2|3}} | <hiero>D22</hiero>| align=right| era=default}}

[[Mathematical notation]] was decimal, and based on hieroglyphic signs for each power of ten up to one million. Each of these could be written as many times as necessary to add up to the desired number; so to write the number eighty or eight hundred, the symbol for ten or one hundred was written eight times respectively.{{sfnp|Clarke|Engelbach|1990|p=217}} Because their methods of calculation could not handle most fractions with a numerator greater than one, they had to write [[Egyptian fraction|fractions]] as the sum of several fractions. For example, they resolved the fraction ''two-fifths'' into the sum of ''one-third'' + ''one-fifteenth''. Standard tables of values facilitated this.{{sfnp|Clarke|Engelbach|1990|p=218}} Some [[Vulgar fraction|common fractions]], however, were written with a special glyph—the equivalent of the modern two-thirds is shown on the right.{{sfnp|Gardiner|1957|p=197}}

Ancient Egyptian mathematicians knew the [[Pythagorean theorem]] as an empirical formula. They were aware, for example, that a triangle had a right angle opposite the [[hypotenuse]] when its sides were in a 3–4–5 ratio.{{sfnp|Strouhal|1989|p=241}} They were able to estimate the area of a [[circle]] by subtracting one-ninth from its diameter and squaring the result:

:Area ≈ [({{frac|8|9}})''D'']<sup>2</sup> = ({{frac|256|81}})''r''<sup>2</sup> ≈ 3.16''r''<sup>2</sup>,

a reasonable approximation of the formula {{nowrap|'''[[Pi|π]]'''''r''<sup>2</sup>}}.{{sfnmp|1a1=Strouhal|1y=1989|1p=241|2a1=Imhausen|2y=2007|2p=31}}