14 Proceedings of the Royal Physical Society. 



discoveries made by Von Helmont, one of the most important 

 was the discovery of the gas which we in the present day 

 call carbonic acid, but which he named gas silvestre. This 

 substance, he tells us, is formed during the processes of com- 

 bustion and fermentation, and is found in the Grotto of the 

 Dog near Naples. By Helmont's labours a very great deal 

 was done in the way of overthrowing old erroneous ideas, 

 and although he did not accomplish exactly all which we — 

 looking from a coign of vantage — think he might have done, 

 we must acknowledge that he prepared the way for a decided 

 forward movement being advantageously undertaken. Un- 

 fortunately, however, his discoveries were not fully utilised, 

 and in point of fact many of the most valuable of them were 

 neglected and forgotten. 



Contemporary with Helmont was the well-known medical 

 chemist, Glauber. Glauber had a happy knack of picking up 

 and examining things which other people threw away, which 

 peculiarity led, among other things, to the discovery of the 

 salt which has for long borne his name. This salt is now 

 rightly known as sodium sulphate, but it will be long before 

 the old-fashioned familiar title, Glauber salt, is forgotten. 

 Like a great many other philosophers of his age, Glauber 

 unfortunately wasted a deal of time in a determined search 

 for the philosopher's stone, and though he undoubtedly dis- 

 covered some useful medicines, it does not appear that he 

 promoted in any very signal manner the progress of chemical 

 science. 



About the time of Glauber's death, Nicholas Lemery, a 

 French chemist, published a work which became exceedingly 

 popular, and which influenced greatly the progress of the 

 science. In this work there appeared for the first time a 

 statement of the distinction between substances of animal 

 origin and those of vegetable origin ; and so we may say that 

 as early as 1675 was the division which we still in a sense 

 retain between organic and inorganic chemistry instituted. 

 Lemery regarded earth and water as elements, and it was not 

 until the distinguished philosopher Eobert Boyle, who was 

 born in Lismore, Ireland, in the year 1627, began his re- 

 searches, that the absurd theories of Aristotle concerning the 



