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Graaf. Sylvius regarded the processes in the human body as chemical, 

 and of the nature of those that occur outside the body in chemical 

 experiments. The process was of the nature of a fermentation, but 

 this word was not used in the same sense as applied by Van 

 Helmont. In fact this word " fermentation " had very varied meanings, 

 according to the author who used it. R. Vieussens, as we have 

 already noted, wrote a long dissertation on this subject. Sylvius was 

 the founder of the iatro-chemical school, as opposed to the iatro- 

 mechanical. He at least directed attention to the importance of 

 chemical processes in the explanation of the phenomena of living 

 beings. 



The fact that some glands possessed ducts and poured their 

 juices into the intestinal canal arrested his attention, and accordingly 

 one of his pupils conducted an investigation on the pancreas in 1664. 

 The pancreatic duct, which still bears his name, was discovered by 

 Wirsung in 1642, the duct of the sub-maxillary gland by Thomas 

 Wharton in 1655-6, and that of the parotid gland by Stensen in 1661. 

 Of the last we have already recorded the story. JOHN GEORGE 

 WIRSUNG was Professor of Anatomy in Padua, and was therefore 

 a remote successor of Vesalius and Fabricius. According to CI. 

 Bernard, he sent a copy of a copper-plate engraving of the duct to 

 Riolan in 1643. He was assassinated on the 22nd August, 1643. 

 Whereon CI. Bernard remarks, in his famous lecture Pancreas, 

 Historique, 23rd May, 1855 : "Nous constatons de nouveau ici que les 

 decouvertes anatomiques et physiologiques suscitent aujourd'hui moins 

 de passions." There is a magnificent figure of this duct in De 

 Graaf 's work copied from that of Sylvius (1695), showing with a 

 softness and delicacy a triumph of the engraver's art. It also shows 

 justly how the smaller secretory ducts join the main duct nearly at 

 a right angle. 



THOMAS WHARTON. 



1614-1673. 



THE publication in 1656 of the Adenographia of Wharton, a 

 Yorkshireman, marks an important epoch in anatomical dis- 

 covery. It deals not only with glands without ducts, e.g. thymus, 

 but, also with his own discovery of the duct of the sub-maxillary gland. 

 He gives careful descriptions of all these glands, their nerves, blood- 

 vessels, &c. The results were originally given in his lectures at the 

 College of Physicians in 1652. I have reproduced his two figures of 

 the sub-maxillary gland of the ox, as he was the first to discover the 

 duct of a salivary gland. He recognised that it conducted saliva, 



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