10 



of the xvater of potassa, which is well known ta 

 have a strong affinity for carbonic acid. A quantity 

 of mercury was now poured into the saucer, and 

 the jar was kept steady by a weight laid upon it. 

 The whole was then set aside in a room, where the 

 barometer stood at 29.3 inches, and the thermome- 

 ter at 62.5. By the following day, the peas had 

 sprouted about l-4th of an inch, the mercury in the 

 saucer had risen 3-10ths of an inch into the jar ; 

 and as the small cup with its- solution floated on the 

 mercury, it was necessarily raised into the jar with 

 it. By the end of the second day, the radicles were 

 S-4ths of an inch long, and the mercury had risen 

 nearly 7-10ths of an inch into the jar, as appeared 

 by a small paper scale, graduated to inches and 

 tenths, and pasted on the outside of the jar. At the 

 close of the third day, the radicles were to appear- 

 ance about an inch long, and the mercury in the 

 jar was nearly an inch in height. And by the fourth 

 day, the radicles had made little additional progress, 

 but the mercury stood nearly 1.1 inch in the jar. 

 During the following day, no apparent changes oc- 

 curred, and the mercury in the jar was now exactly 

 1.1 inch in height, when that in the saucer was 

 brought to a level with it. The barometer at this 

 period was 29.95, and the thermometer 65. 



9. Having by other experiments ascertained, that 

 when the mercury had reached this elevation, and 

 became stationary, the oxygen gas of the air em- 

 ployed had completely disappeared, we proceeded 

 to determine the proportion which this diminution 

 In the bulk of air, evinced by the rising of the mer- 

 cury, bore to that of the oxygen gas which the air 



