( 48 ) 



JEAN B. VAN HELMONT. 



THERE was born at Brussels, in 1577, one who exercised a great 

 influence on the rise of chemical doctrine viz., Jean Baptiste van 

 Helmont, who, after trying various studies, was attracted to 

 medicine and graduated as M.D. in 1 599. He had by marriage ample 

 pecuniary resources ; and lived at Vilvorde, where he died in 1644. He 

 introduced two new terms, " gas " and " bias." The latter perhaps 

 corresponded to the archams of Paracelsus. The term "gas" he 

 applied to something which is like air, but is not the air of the atmo- 

 sphere. He discovered it as a product of fermentations — gas 

 sylvestre. He obtained it when charcoal was burned, a kind of 

 spirit — a " geist." Geist, ghost, and gas are the same words. He saw 

 that changes took place in the juice of the grape, and he assumed that 

 this was brought about by a ferment, causing ebullition. Imbued 

 with this idea of fermentation, he regarded all the processes in the 

 economy, not only digestion in the intestinal tract, but all other changes 

 of nutrition, as due to this process. His researches gave an impulse to 

 the study of the chemical aspect of certain problems in physiology. 

 The scene is now shifted to Holland. 



FRANCISCUS SYLVIUS. 



1614— 1672. 



SYLVIUS DE LA BOE, a Frenchman by descent and a 

 Dutchman by adoption, was the great leader of the chemical 

 sect. He graduated in medicine at Basel in 1637, and practised 

 at Amsterdam, where he became familiar with the views of 

 Descartes and Van Helmont. In 1658 he was appointed Professor 

 of Medicine at Leyden, where he exerted a powerful influence on 

 some of his celebrated pupils. He is said to have been the first to 

 introduce the plan of giving lectures on his own individual cases 

 in the hospital, a practice followed later with great success by 

 Boerhaave. Moreover he seems to have been the first to found a 

 University chemical labor atorium. His bias was towards chemical 

 speculation and investigation. He adopted Harvey's view of the 

 circulation of the blood. The " aqueduct of Sylvius " is named after 

 him. He distinguished between conglomerate and conglobate glands. 

 Amongst his pupils were N. Stensen, of whom wte have already 

 spoken, and Regner de Graaf, or, as Stokvis calls him, Reinier de 



