year 1771, Dr. Priestley, who had been employed in chemical pursuits, detected various aerial fluids totally unknown before. Dr. Black traced the laws of latent heat, and discovered the carbonic acid. The science of electricity was as it were created, and thunder was drawn from the clouds; in short, the properties of the atmosphere were examined with accuracy and ascertained.
In the year 1781, Mr. Cavendish proved that water is not a simple element, but is composed of the bases of two gases.
All these new discoveries embarrassed the votaries of the doctrine of Stahl, and the conclusions to which they led, were of such a nature as to contradict many of the acknowledged laws of the science. A crowd of new and extraordinary chemical tacts succeeded each other with astonishing rapidity; academical memoirs and periodical publications were scarcely sufficient to publish all the new discoveries that were made. The chemical laws of nature were submitted to the test of weight, measure, and vision. The totality of the experiments of different kinds, and instituted for various purposes, laid before the public by individuals at that time, forms a mass of immense extent, and presents one of the most prominent features of the age: the science of chemistry engaged general attention; and yet, whilst it became enriched with such great and important facts, its theory proceeded but slowly. It even appeared to acquire a retrograde motion, or to lose ground, and become embarrassed among these immense acquisitions. Every chemist had his own theory; for many of the new facts proved hostile to the acknowledged doctrines of the science; and the conclusions to which they led, were of such a nature as to puzzle and contradict the most important chemical laws: there was, therefore, neither system nor connection between the chemical facts, the multiplicity of which actually overwhelmed its theory. A man of an extraordinary mind was wanting, who might profit by this stale of uncertainty and indecision, to arrest the vacillations of this science. A revolution was prepared in every quarter, but no one had yet felt bold enough to regulate its motion: it was therefore requisite to proceed one step further, that the imperfect system of chemistry then prevailing might be exploded for ever. This was effected by the genius of a foreign chemist, whose name was Lavoisier; a man endued with the most profound talents for science: enabled by means of his own princely fortune, and the liberal bounty of the French government, he instituted a series of ingenious experiments, the results of which proved to demonstration, that the theory of phlogiston was founded in error. His experiments were repeated by all the philosophers of Europe; his reasonings and inferences were attacked by the defenders of the phlogistic theory: a kind of chemical war was thus kindled in the republic of letters, which was carried on with great violence and animosity; and posterity will view with regret, men of undoubted genius at times divesting themselves of the armour of truth and candour, and endeavouring to stub their adverse fellow-la-
