The extraction of oil from whales is a very ancient process, but no regular oil production existed until the Basques started the whaling industry in the twelfth and thirteenth centuries. With their primitive equipment, they only made use of the blubber, the part of the whale richest in oil. The blubber was cut up into small pieces which were cooked in open iron cauldrons. This method was in use until the beginning of the present century, when less wasteful methods were introduced in order to utilise as much as possible of the carcass. Flesh, entrails and bones are now cooked in closed boilers under increased pressure and temperature, and since about 1925 a combined steam and mechanical treatment of the material, known as “apparatus cooking”, has resulted in still more efficient extraction.