Casein, from skim milk, used in making buttons and in various industries, and milk sugar, are valuable by-products in the dairy industry. Sugar is not the only useful product from the sugar-cane, for the final molasses residue known as black-strap is a valuable stock food. The spent bone black used in the purification of the cane juice is used for making shoe blacking, and from the Bagasse or crushed cane a very useful insulating building board or an insulating material may be made. In the roasting of coffee, the alkaloid caffein in small quantities is driven off and collects in the flues. This is later purified and is used in various popular carbonated beverages. This list is only suggestive, for there are numerous other byproducts that have been or may be utilized, and it is the task of the chemist and the food manufacturer, to practically apply their knowledge to our food supply, and thus effect a great saving,.