James's Powder is a patent nostrum, which has been in use for upwards of a century as a febrifuge. It was avowed by its inventor to contain antimony; but, as its mode of preparation was kept secret, the exact state in which the antimony existed in the powder was not known. The composition of James's Powder was first examined by Dr George Pearson, who published his experiments in the eighty-first volume of the Philosophical Transactions. He believed it to consist of 43 per cent. of phosphate of lime, and 57 of peroxide of antimony M. Chenevix, in the Phil. Trans. for 1801 gave an account of some experiments which he had made on James's Powder, by which he found it to contain only 44 per cent. of the oxide of antimony. Berzelius, in his Lehrbuch, gives an account of an examination which he had made of a specimen of the powder. He found that about two per cent. was soluble in water, and this he found to consist of antimonite of lime.