It occurred to him that there must be some substance which, mixed with the gum, would render it durable, and he began to experiment with almost every substance that he could lay his hands on. All proved total failures with the exception of magnesia. By mixing half a pound of magnesia with a pound of the gum he produced a substance whiter than the pure gum, which was at first as firm and flexible as leather, and out of which he made beautiful book-covers and piano-covers. It looked as if he had solved the problem; but in a month his pretty product was ruined. Heat caused it to soften; fermentation then set in, and finally it became as hard and brittle as thin glass. His stock of money was now exhausted. He was forced to pawn all his own valuables and even the trinkets of his wife. But he felt sure that he was on the road to success and would eventually win both fame and fortune. He removed his family to the country, and set out for New York, where he hoped to find someone willing to aid him in carrying his experiments further. Here he met two acquaintances, one of whom offered him the use of a room in Gold Street as a workshop, and the other, a druggist, agreed to let him have on credit such chemicals as he needed. He now boiled the gum, mixed with magnesia, in quicklime and water, and as a result obtained firm, smooth sheets that won him a medal at the fair of the American Institute in 1835. He seemed on the point of success, and easily sold all the sheets he could manufacture, when, to his dismay, he discovered that a drop of the weakest acid, such as the juice of an apple or diluted vinegar, would reduce his new compound to the old sticky substance that had baffled him so often. His first important discovery on the road to real success was the result of accident. He liked pretty things, and it was a constant effort with him to make his productions as attractive to the eye as possible. Upon one occasion, while bronzing a piece of rubber cloth, he applied aqua fortis to it for the purpose of removing part of the bronze. It took away the bronze, but it also destroyed the cloth to such a degree that he supposed it ruined and threw it away. A day or two later, happening to pick it up, he was astonished to find that the rubber had undergone a remarkable change, and that the effect of the acid had been to harden it to such an extent that it would now stand a degree of heat which would have melted it before. Aqua fortis contained sulphuric acid. Goodyear was thus on the threshold of his great discovery of vulcanizing rubber. He called his new process the "curing" of india-rubber.