S4 Biographical Account of [Aug. 



pneumatic chemistry before his publication. He states the facts 

 ascertained by Van Helmont, Boyle, Hales, Boerhaave, Stahl, 

 Venel, Black, Saluces, Macbiide, Cavendish, and Priestley; and 

 gives ns an account of Meyer's theory of calcination, and the 

 cause of causticity in lime and alkalies, the defence of this 

 theory by Crans and de Smeth, and its refutation by Jacquin. 

 In the second part he relates a number of experiments of his 

 own, chiefly relative to Dr. Black's theory of the difference 

 between quick- lime and lime-stone, and of the cause of the 

 causticity in alkalies. He demonstrates the existence of carbonic 

 acid in the mild alkalies, and in calcareous spar ; shows that it 

 has the propertv of combining with the alkaline and earthy 

 bases, and with metallic oxides. He ascertains the effect of 

 this gas upon animals and upon combustion, and shows that 

 water absorbs it. His experiments, though satisfactory as to the 

 truth of Dr. Black's theor) r , are not to be compared to the pre- 

 ceding experiments on the same subject made by Mr. Cavendish, 

 which are greatly superior both in point of accuracy and value. 

 He terminates the volume by some experiments. on the combus- 

 tion of phosphorus, in which he shows that phosphorus absorbs 

 a portion of the air, that it will not burn without air, and that 

 it will not become acid without absorbing air. He shows the 

 same thing with respect to sulphur, and he says that gunpowder 

 will not burn in vacuo. How he fell into this mistake it is not 

 easy to say. The contrary had been proved long before by 

 Haukesbee, Robins, &c. He made some experiments on air, 

 in which phosphorus has burnt out, and shows that it is not the 

 same as carbonic acid gas. From these observations we see that 

 he was on the way to his particular theory of combustion ; 

 though the ignorance of oxygen, or of the nature of air, pre- 

 vented his views from being cither steady or correct. 



Though I have mentioned this volume of essays in the first 

 place, because it was published by itself, yet it was not the first 

 of M. Lavoisier's works. His other dissertations were published 

 in the Memoirs of the French Academy, in the Journal de 

 Physique, and in the Annates de Chimie. I shall notice them 

 as nearly as possible in the order of their dates, thorgh this is 

 attended with considerable difficulty ; because the Memoirs of 

 the Academy were often published, and even contain papers 

 written several years after the date upon the title page, and 

 abstracts of his papers sometimes made their appearance in the 

 Journal de Physique before they were published in the Memoirs 

 of .the Academy. I may therefore now and then commit an 

 error with respect to date ; but in most cases this is immaterial. 



2. His first paper in the Memoirs of the Academy is upon 

 Gypsum. It will be found in the volume for 17<>8. He gives 

 an account of the properties of gypsum at great length, and 





