The United States uses three-fourths of the world's rubber output and grows none of it. What is the use of tropical possessions if we do not make use of them? The Philippines could grow all our rubber and keep a $300,000,000 business under our flag. Santo Domingo, where rubber was first discovered, is now under our supervision and could be enriched by the industry. The Guianas, where the rubber tree was first studied, might be purchased. It is chiefly for lack of a definite colonial policy that our rubber industry, by far the largest in the world, has to be dependent upon foreign sources for all its raw materials. Because the Philippines are likely to be cast off at any moment, American manufacturers are placing their plantations in the Dutch or British possessions. The Goodyear Company has secured a concession of 20,000 acres near Medan in Dutch Sumatra.
While the United States is planning to relinquish its Pacific possessions the British have more than doubled their holdings in New Guinea by the acquisition of Kaiser Wilhelm's Land, good rubber country. The British Malay States in 1917 exported over $118,000,000 worth of plantation-grown rubber and could have sold more if shipping had not been short and production restricted. Fully 90 per cent. of the cultivated rubber is now grown in British colonies or on British plantations in the Dutch East Indies. To protect this monopoly an act has been passed preventing foreigners from buying more land in the Malay Peninsula. The Japanese have acquired there 50,000 acres, on which they are growing more than a million dollars' worth of rubber a year. The British Tropical Life says of the American invasion: "As America is so extremely wealthy Uncle Sam can well afford to continue to buy our rubber as he has been doing instead of coming in to produce rubber to reduce his competition as a buyer in the world's market." The Malaya estates calculate to pay a dividend of 20 per cent. on the investment with rubber selling at 30 cents a pound and every two cents additional on the price brings a further 3-1/2 per cent. dividend. The output is restricted by the Rubber Growers' Association so as to keep the price up to 50-70 cents. When the plantations first came into bearing in 1910 rubber was bringing nearly $3 a pound, and since it can be produced at less than 30 cents a pound we can imagine the profits of the early birds.
The fact that the world's rubber trade was in the control of Great Britain caused America great anxiety and financial loss in the early part of the war when the British Government, suspecting—not without reason—that some American rubber goods were getting into Germany through neutral nations, suddenly shut off our supply. This threatened to kill the fourth largest of our industries and it was only by the submission of American rubber dealers to the closest supervision and restriction by the British authorities that they were allowed to continue their business. Sir Francis Hopwood, in laying down these regulations, gave emphatic warning "that in case any manufacturer, importer or dealer came under suspicion his permits should be immediately revoked. Reinstatement will be slow and difficult. The British Government will cancel first and investigate afterward." Of course the British had a right to say under what conditions they should sell their rubber and we cannot blame them for taking such precautions to prevent its getting to their enemies, but it placed the United States in a humiliating position and if we had not been in sympathy with their side it would have aroused more resentment than it did. But it made evident the desirability of having at least part of our supply under our own control and, if possible, within our own country. Rubber is not rare in nature, for it is contained in almost every milky juice. Every country boy knows that he can get a self-feeding mucilage brush by cutting off a milkweed stalk. The only native source so far utilized is the guayule, which grows wild on the deserts of the Mexican and the American border. The plant was discovered in 1852 by Dr. J.M. Bigelow near Escondido Creek, Texas. Professor Asa Gray described it and named it Parthenium argentatum, or the silver Pallas. When chopped up and macerated guayule gives a satisfactory quality of caoutchouc in profitable amounts. In 1911 seven thousand tons of guayule were imported from Mexico; in 1917 only seventeen hundred tons. Why this falling off? Because the eager exploiters had killed the goose that laid the golden egg, or in plain language, pulled up the plant by the roots. Now guayule is being cultivated and is reaped instead of being uprooted. Experiments at the Tucson laboratory have recently removed the difficulty of getting the seed to germinate under cultivation. This seems the most promising of the home-grown plants and, until artificial rubber can be made profitable, gives us the only chance of being in part independent of oversea supply.
There are various other gums found in nature that can for some purposes be substituted for caoutchouc. Gutta percha, for instance, is pliable and tough though not very elastic. It becomes plastic by heat so it can be molded, but unlike rubber it cannot be hardened by heating with sulfur. A lump of gutta percha was brought from Java in 1766 and placed in a British museum, where it lay for nearly a hundred years before it occurred to anybody to do anything with it except to look at it. But a German electrician, Siemens, discovered in 1847 that gutta percha was valuable for insulating telegraph lines and it found extensive employment in submarine cables as well as for golf balls, and the like.
Balata, which is found in the forests of the Guianas, is between gutta percha and rubber, not so good for insulation but useful for shoe soles and machine belts. The bark of the tree is so thick that the latex does not run off like caoutchouc when the bark is cut. So the bark has to be cut off and squeezed in hand presses. Formerly this meant cutting down the tree, but now alternate strips of the bark are cut off and squeezed so the tree continues to live.
When Columbus discovered Santo Domingo he found the natives playing with balls made from the gum of the caoutchouc tree. The soldiers of Pizarro, when they conquered Inca-Land, adopted the Peruvian custom of smearing caoutchouc over their coats to keep out the rain. A French scientist, M. de la Condamine, who went to South America to measure the earth, came back in 1745 with some specimens of caoutchouc from Para as well as quinine from Peru. The vessel on which he returned, the brig Minerva, had a narrow escape from capture by an English cruiser, for Great Britain was jealous of any trespassing on her American sphere of influence. The Old World need not have waited for the discovery of the New, for the rubber tree grows wild in Annam as well as Brazil, but none of the Asiatics seems to have discovered any of the many uses of the juice that exudes from breaks in the bark.
The first practical use that was made of it gave it the name that has stuck to it in English ever since. Magellan announced in 1772 that it was good to remove pencil marks. A lump of it was sent over from France to Priestley, the clergyman chemist who discovered oxygen and was mobbed out of Manchester for being a republican and took refuge in Pennsylvania. He cut the lump into little cubes and gave them to his friends to eradicate their mistakes in writing or figuring. Then they asked him what the queer things were and he said that they were "India rubbers."
FOREST RUBBER