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Diversion dam — The first Diversion dam is Sadd el-Kafara Dam built in Egypt around 2700 B.C. [19]; Noria — Norias appeared in Egypt in the 4th Century B.C. [20]; Beekeeping — domesticated Beekeeping was first recorded in ancient Egypt around 2600 B.C. [21] [22] as well as the first use of smoke while extracting the honey from bee nests.
Ancient Egyptian technology describes devices and technologies invented or used in Ancient Egypt. The Egyptians invented and used many simple machines, such as the ramp and the lever, to aid construction processes. They used rope trusses to stiffen the beam of ships.
Remains from ancient China (dating 4000 years ago) have carved bamboo pegs, tapped into the bone, to replace lost teeth, and 2000-year-old remains from ancient Egypt have similarly shaped pegs made of precious metals. Some Egyptian mummies were found to have transplanted human teeth, and in other instances, teeth made of ivory.
Moreover, the ancient historian Herodotus wrote that influential rulers like Cyrus and Darius employed Egyptian physicians, indicating the high esteem in which Egyptian medical practitioners were held. These physicians documented their treatments, allowing their knowledge to be passed down through generations, and it has been found that many of ...
A man brushing his teeth while looking in a mirror. Tooth brushing is the act of scrubbing teeth with a toothbrush equipped with toothpaste.Interdental cleaning (with floss or an interdental brush) can be useful with tooth brushing, and together these two activities are the primary means of cleaning teeth, one of the main aspects of oral hygiene. [1]
The practice of water treatment soon became mainstream, and the virtues of the system were made starkly apparent after the investigations of the physician John Snow during the 1854 Broad Street cholera outbreak demonstrated the role of the water supply in spreading the cholera epidemic. [78]
Water softeners, which use sodium ions to replace water-hardening minerals in water, were first introduced into the water treatment market in 1903. The theory of ion exchange involves replacing undesirable or potentially harmful ions with more desirable or harmless ones. This is implemented in domestic water treatment system as water softeners.
Other cultures such as the Egyptians were using alum as a means of removing suspended particles by 1500 B.C. [1] Medieval Venice obtained filtered water from cisterns using beds of sand. [2] Throughout most of human history, the primary means of acquiring untainted water was to avoid the problem and bring in water from an outside source that ...