Waterskin

A waterskin is a receptacle used to hold water. Normally made of a sheep or cow bladder, it retains water naturally and therefore was very useful in desert crossings up until the invention of the canteen. It is still used in some developing nations. Though it may have been used over 5000 years ago by tribal peoples, the first pictures of it are from ancient Assyrians, who used the bladders as floats in 3000 B.C. It also was used by large ancient empires such as Rome before the advent of the canteen.