CARTILAGE consists of chondrine, a substance somewhat like gelatine, and contains also the salts of sulphur, lime, soda, potash, phosphorus, magnesia, and iron. BILE is made up of water, fat, resin, sugar, cholesterine, some fatty acids, and the salts of potash, iron, and soda. THE BRAIN is made up of water, albumen, fat, phosphoric acid, osmazone, and salts. THE LIVER unites water, fat, and albumen, with phosphoric and other acids, and lime, iron, soda, and potash. THE LUNGS are formed of two substances: one like gelatine; another of the nature of caseine and albumen, fibrine, cholesterine, iron, water, soda, and various fatty and organic acids. How these varied elements are held together, even science with all its deep searchings has never told. No man, by whatsoever combination of elements, has ever made a living plant, much less a living animal. No better comparison has ever been given than that of Youmans, who makes a table of the analogies between the human body and the steam-engine, which I give as it stands. ANALOGIES OF THE STEAM-ENGINE AND THE LIVING BODY. _The Steam Engine in Action takes_: 1. Fuel: coal and wood, both combustible. 2. Water for evaporation. 3. Air for combustion. _And Produces_: 4. A steady boiling heat of 212° by quick combustion. 5. Smoke loaded with carbonic acid and watery vapor. 6. Incombustible ashes. 7. Motive force of simple alternate push and pull in the piston, which, acting through wheels, bands, and levers, does work of endless variety. 8. A deficiency of fuel, water, or air, disturbs, then stops the motion. _The Animal Body in Life takes_: 1. Food: vegetables and flesh, both combustible. 2. Water for circulation. 3. Air for respiration. _And Produces_: 4. A steady animal heat, by slow combustion, of 98°. 5. Expired breath loaded with carbonic acid and watery vapor. 6. Incombustible animal refuse. 7. Motive force of simple alternate contraction and relaxation in the muscles, which, acting through joints, tendons, and levers, does work of endless variety. 8. A deficiency of food, drink, or air, first disturbs, then stops the motion and the life.