Leather was a solution for hoses and plumbing

We already know that leather can float and inflate, and that it was historically used as vessels for water and drinks. The historian Strabo informs us of another application: the Phoenicians, who lived on the coasts of the Mediterranean (particularly in the east), used leather in their plumbing. Leather hoses allowed the Phoenicians to get water to cities, particularly in cases of war and drought. Water hoses made from leather were, therefore, a useful application in a hot climate.  

Leather has since been used in plumbing or to make hoses. Leather would be used in old water pumps to block the passage of water and as a working plunging component within the pumping mechanism. Today, fire hoses are made with rubber on a fabric backing. Fires were originally put out using buckets of water; however, the first fire hoses were made from leather.

To this day, leather components are used in our plumbing, and specialized tanning can help make leather fully waterproof. Leathers ability to withstand almost anything and resist chafing or other forms of light damage, makes it perfect for plumbing application. There is no surprise that there are still leather parts we use in plumbing today, although it is now only used for small parts, such as the rings to prevent leaking taps.