gas of the air employed was consumed by vegetation, 
of which sevea parts existed in the state of carbonic 
acid at the time of examination, and the remaining 
three parts may reasonably be supposed to have been 
attracted, in the state of acid gas, partly by the water 
over which the vessel was inverted, and partly by 
that through which it was passed, when submitted to 
examination, 
236. On the 26th of July we raised a second jar, 
under which cuttings of willow had been confined, 
and in which, also, a small quantity of solution of po- 
tassa had been placed. Into this jar the water had 
risen half an inch, and, on pouring diluted sulphuric 
acid into the alkaline solution, a very brisk efferves- 
cence was excited. In a third jar, where a similar 
quantity of solution had been inclosed, the same 
phenomena were exhibited. In a fourth jar, ^V of 
the oxygen gas were consumed. In a fifth, where 
nine similar cuttings of willow were placed in a large 
mouthed phial under a jar containing 73 cubic inches 
of atmospheric air, the air, on being examined on the 
5th day, lost -rVo by lime water, which it rendered mil- 
ky, and the residue lost seven parts more by the slow 
combustion of phosphorus. Allowing also a little acid 
gas to have been attracted by the water during the 
analysis, we are enabled to account for the whole 
oxygen which the air originally contained, of which 
jr had been converted into carbonic acid, and T^ 
remained at the time the analysis by phosphorus 
was made. In these experiments, therefore, no sub- 
stance, except the vegetables, was present, which 
could, in the smallest degree, affect the air ; and the 
results correspond entirely with those already given* 
