Years passed, and still Böttgher made no gold; but he was not hung. It was reserved for him to make a far more important discovery than the conversion of copper into gold, namely, the conversion of clay into porcelain. Some rare specimens of this ware had been brought by the Portuguese from China, which were sold for more than their weight in gold. Böttgher was first induced to turn his attention to the subject by Walter von Tschirnhaus, a maker of optical instruments, also an alchemist. Tschirnhaus was a man of education and distinction, and was held in much esteem by Prince Fürstenburg as well as by the Elector. He very sensibly said to Böttgher, still in fear of the gallows—“If you can’t make gold, try and do something else; make porcelain.” The alchemist acted on the hint, and began his experiments, working night and day. He prosecuted his investigations for a long time with great assiduity, but without success. At length some red clay, brought to him for the purpose of making his crucibles, set him on the right track. He found that this clay, when submitted to a high temperature, became vitrified and retained its shape; and that its texture resembled that of porcelain, excepting in colour and opacity. He had in fact accidentally discovered red porcelain, and he proceeded to manufacture it and sell it as porcelain. Böttgher was, however, well aware that the white colour was an essential property of true porcelain; and he therefore prosecuted his experiments in the hope of discovering the secret. Several years thus passed, but without success; until again accident stood his friend, and helped him to a knowledge of the art of making white porcelain. One day, in the year 1707, he found his perruque unusually heavy, and asked of his valet the reason. The answer was, that it was owing to the powder with which the wig was dressed, which consisted of a kind of earth then much used for hair powder. Böttgher’s quick imagination immediately seized upon the idea. This white earthy powder might possibly be the very earth of which he was in search—at all events the opportunity must not be let slip of ascertaining what it really was. He was rewarded for his painstaking care and watchfulness; for he found, on experiment, that the principal ingredient of the hair-powder consisted of _kaolin_, the want of which had so long formed an insuperable difficulty in the way of his inquiries.