EXPERIMENTS OF GASES ABSORBED BY WATER. 237 



globe, of the rapacity of 117^ cubical inches, was filled with 

 water frefti from the well. To its month was adapted a curved 

 and ftoppered tube, which held £ of an inch ; and this was alfo 

 filled with water. The globe was then placed in a vefTel of 

 brine, which was kept boiling between fix and feven hours:; 

 and the gafes were received over mercury. Their quantity 

 and quality were as follows. 



5.38, total gas from 117| inches of water. 



But, 4^ inches of water were expelled, owing to the ex- 

 panfion by heat. Therefore 117| — 4£ = 113 inches of 

 wafer, gave 5.38 inches of gas; and 100 inches, confe- 

 quently, gave 4.76, of which 3.38 were carbonic acid, and 

 1.38 atmofpherical air. Hence, the water afforded about -^ , 



its bulk of atmofpherical air, and ■—-. of a mixture of gafes. 

 In this eftimate, the gas remaining in the tube is reckoned as 

 Carbonic acid, which may be allowed, fince the portion laft 

 obtained held only -^ its bulk of common air. 



SECTION II. 



ON THE INFLUENCE OF PRESSURE IN PROMOTING THE 

 ABSORPTION OF GASES; AND THE DESCRIPTION OF AN 

 APPARATUS FOR EXHIBITING THIS PHENOMENON. 



For the purpofe of determining the ratio between the addi- Method of ope* 

 tion of preflure and the increafed abforption of gafes by water, g a fes wereab- 6 

 I employed the apparatus, with fome addition, which has been forbe \ under 

 already defcribed. The tube B was lengthened at pleafure, pre ure * 

 with the view of obtaining, by a column of mercury, any ad- 

 ditional prelfure that might be required. The veflel A, Fig. 1, 



