their furnaces, they produced those materials upon which the true doctrine of this science was afterwards erected; for as yet it did not exist. Many of the followers of Paracelsus were greatly devoted to the study of chemistry; but the absurd, ridiculous, and unprincipled conduct of their master, tended materially to bring the views and speculations of the alchemists into deserved and general disrepute.
At the end of the seventeenth century, chemistry began to assume a scientific form. The scattered facts which the alchemists had discovered, were collected, arranged, and reduced to principles, so that the knowledge of them might be applied to useful purposes. The task was accomplished by Becker. This man collected all the discoveries which were noticed before him, and pointed out many important objects to which the researches of chemists ought to be directed. It was the first dawn of chemical science, and the publication of his Physica Subterranea, in the year 1669, forms a very important æra in the history of chemical philosophy.
At this period chemistry escaped for ever from the toils of alchemy, and the rudiments of the science which we find it at present were developed. Becher distinguished himself so highly by his chemical knowledge, that the names of all the former theorists seem to be forgotten: after having laid the foundation of the famous system of phlogiston, he died in the year 1682.
The facts which had been accumulated by the labours of the alchemists, and to which Becher had given a systematic form, were soon after methodized and extended by his pupil Stahl. Indeed, this man simplified and improved the doctrines of his master so much, that he made it almost wholly his own; and hence it been known ever since by the name of the Stahlean Theory.
He was the first who had a clear notion of chemical union, and gives many instances of complicated chemical processes absolutely scientific. His writings have made him immortal, and place him among the first characters of the age in which he lived. His theory was universally received by chemists, and continued to flourish for more than half a century. He died 1704. Since this period, chemistry has been cultivated with still greater success. Men of eminence have appeared every where, and discoveries been multiplied, which have led to important events.
Towards the middle of the eighteenth century this study became general, and even fashionable, particularly in France and Germany. The names of Beaume, Rouelle, Margraaf, Scheele, Berquos, &c. will long remain, distinguished in the annals of chemical science.
The spirit of enquiry which these philosophers had excited, appears to have summoned into action the faculties of the most learned men in Europe; and from this time the progress of chemistry was rapid and brilliant, facts and discoveries were daily multiplied, and a spirit of enthusiasm for the study burst forth, and was diffused far and wide. Several of the invisible agents which are of so much importance in the economy of nature, were discovered. In the C2