When the art of embalming began no one knows, but it certainly dates back to the building of the Pyramids. We know that when Jacob died in Egypt, his son Joseph had him embalmed and the Bible says it took forty days to do the job properly. It also relates that when Joseph died the Egyptians embalmed him and put him away in a coffin. Herodotus, who was one of the best travel writers of all times, describes how embalming was done and tells the details of mummy-making. He says the art was carried on by a special guild, whose members were appointed by the government and who had to work at fixed prices. The bodies were mummified in three different ways. By the first and most costly method, the brains were extracted through the nose by means of an iron probe, and the intestines were taken out through an incision made in the side. The intestines were cleaned and washed in palm wine, covered with aromatic gum, and set aside in jars. The cavity of the body was next filled with spices, including myrrh, cassia, and other fragrant substances, and it was then sewn up. After this it was soaked in a solution of natron, a kind of carbonate of soda, being allowed to lie in it for a couple of months or more. When it had been taken out and wrapped in fine linen so smeared over with gum that it stuck to the skin, the mummy was ready for burial. The second process, though cheaper, took about the same time. In this the brains were not extracted and the body was so treated in a solution that everything except the skin and bones was dissolved. There was a third process which consisted of cleaning the corpse and laying it down in salt for seventy days. The first process cost about twelve hundred dollars; the second, one hundred dollars; and the third, considerably less. Other authorities describe different methods of mummification. Most of the mummies discovered, however, have been preserved by means of gums of some kind and by pitch and carbonate of soda. The mummies prepared with gums are usually green in colour with skins which look as though they were tanned. They often break when they are unrolled. The bodies preserved with pitch are black and hard, but the features are intact, and it is said that such mummies will last forever. In those treated with soda the skin is hard and rather loose, and the hair falls off when it is touched. The pitch mummy ordinarily keeps its hair and teeth.