lAfe and Writings of Lavoijler, 79 



tions, fuch as Obfervations on the propofal for creeling a 

 ft^am engine to fupply the city of Paris with water, on thun- 

 der, on the northern lights, on the tranlition of water into 

 ice, &c. The Memoirs of the Academy for the year 1770 

 contain Obfervations by him on the nature of water, and on 

 the experiments faid to prove the poffibility of its convcrfioa 

 into earth. Lavoifier, however, fliowed that the earth ob- 

 tained by the diftillation of water was a part of the veflel 

 which had been attacked during the operation : for, having 

 continued the diftillation without interruption loi days, the 

 total weight of the veflel and of the water contained in it re- 

 mained unchanged, but the pelican had loft as mucji in 

 weight as the water had increafed. 



In the year 1774 Lavoifier proved that the increafed 

 weight of metals during their oxidation, arofe from their im- 

 bibing the air contained in the veffels in which the operation 

 was performed ; by which means a queftion that had long 

 formed a fubjeft of difpute among philofophers and chemifts, 

 and had occafioned many coftly experiments, was finally de- 

 termined. This formed a foundation for his new chemical 

 theory, which he firft oppofed to the phlogiftic fyftem before 

 adopted by chemifts. 



In the fame year he publiflicd his fmall phyfico-chemical 

 works. Prieftley, in the year 1772, had made known his 

 experiments on carbonic acid gas ; but Lavoifier traced back 

 its origin to Paracelfus, born in 1493, and to his pupil Van 

 Helmont, born in 1588 ; and fhowed that even Paliflev, 

 Ray, Boyle, Hales, Venel and Macbride had been in part 

 acquainted with this gas. He (bowed alfo that Dr. Black of 

 Edinburgh had called the attention of philofophers to this 

 important pan of chemiftry fo early as the year 1756 * ; and 

 therefore he afcribed to him the honour of this new difco- 

 very, which in the courfe of twenty years had given occafion, 

 to fo many others of -the utmoft importance to mankind. 



Lavoifier proved by his experiments, that an elaftic fluid, 

 or kind of gas, was united in a fixed form with calcareous 

 earth ; he proved the prefence of it in alkalies, and fliowed 



♦ Tn EflUys and Obflirvati-nv P: yuc:,' ?- ' I • — Vd. I[. Edin- 

 liurghi':56. 



that 



