would probably have enabled him to anticipate many modern conclusions. He had already recognised some of the transformations of sugar, had analysed alcohol, and had declared that in animal and vegetable chemistry no less than in the inorganic kingdom nothing is ever destroyed, but that vegetation and animalisation are only inverse phenomena of combustion and putrefaction.
Synthetic Organic Compounds.
Some isolated results of the artificial productions of organic substances are recorded which do not seem to have been recognised as challenging the reign of vital force. Scheele, in 1786, formed oxalic acid by oxidising sugar by nitric acid; and in 1822 Döbereiner produced formic acid, previously known as a distillate of ants, by oxidising tartaric acid. In both these cases, however, the transformation was essentially one from a previous organic substance.
The inauguration of synthetic chemistry is understood to date from the year 1828 when Wöhler, then a professor of chemistry at Berlin, produced a supposed cyanate of ammonium by the action of ammonium chloride on silver cyanate. Wöhler was surprised to find the cyanate of ammonium which he had obtained did not correspond with other ammonium salts, but resembled, and as he afterwards proved, was identical with the organic substance, urea, a crystalline compound which constitutes about half of the solid matter dissolved in urine. Wöhler and Liebig next collaborated in a study of organic substances, and one of the early results of their investigations was the discovery of the compound radical, benzoyl, as they termed it, C7H5O, which they
