Although so much in evidence about us, India rubber is not by any means a cheap material. Costing only five cents a pound when Goodyear commenced his experiments, it is now worth a dollar a pound, and is therefore much more expensive than any of the ordinary metals, woods, or building materials. Many substitutes in the form of compositions of various ingredients have been devised and patented, but no real substitute for nature’s product has yet been found. For many years old and worn out rubber goods were thrown away as worthless. Now all such rubber is reclaimed, and used in many grades of goods which do not require a pure gum. Insatiable as the demands of the trade may appear, there is no need to fear a rubber famine, for the forests of trees in South America and the East Indies are practically inexhaustible, and in the rich alluvial soil of their habitat nature’s processes of growth rapidly restore the decimation. [Illustration: FIG. 163.--MAKING RUBBER SHOES.] Since the time of Goodyear, the amplification of this art and the multiplication of uses for rubber, and its increased commercial importance, have gone on at such a rate of increase that to-day we may be said to be living in the rubber age. Its uses and applications are legion, and they extend literally from the cradle to the grave. When the baby comes into the world its introduction to India rubber begins at once with the nursing bottle and the gum cloth, and when the aged invalid takes leave of the world his last moments are soothed with the water bag and the rubber bed, and between these extremes we find it in evidence everywhere about us. In wearing apparel it extends from the crown of the head to the sole of the foot--rubber cap, coat, gloves, and shoes. The man has it in his suspenders and his pipe stem, the woman in her garters and dress shields, and the baby in its teething ring and rattle. The soldier stands on picket duty in the rain, and the rubber blanket protects him from rheumatism. If wounded, the surgeon dresses his mangled limb with rubber bandages, and when he gets well he has a rubber cushion on the end of his crutch, or on the foot of his artificial leg. If wounded in the mouth perhaps the government gives him a set of artificial teeth on a rubber plate. The rubber mat greets you at the front door, a little pad cushions the door stops and the backs of chairs, and a ring seals the mouth of the fruit jar. The whole array of toilet articles, including combs, brushes, mirrors, shoe horns, etc., are made from it. In the parlor it is found in picture frames and the piano cover; in the bath room the wash rag, water bag, rubber cup, and hose pipe of the shower bath are all made of it; in the play room are found rubber balls and toys of all kinds; in the kitchen the clothes wringer and the table cloth; in the dining room the handles of knives, and the tea tray, and what is more useful and more ubiquitous in the