from Water exposed to Light. 229 



Quantity. Quality. 



By the green water in the globe A, -^-fa of a cubic inch 280 degrees 

 " " " " " B, ^ " " 241 " 



By the spring-water in the globe C, ^ y " " 68 " 



The waters in these experiments were made to boil but 

 for a moment; otherwise it is probable more- air might 

 have been separated from them. 



Finding that fresh leaves, exposed to the action of 

 the sun's rays, in water which had already turned green, 

 caused pure air to be separated from the water in so great 

 abundance, I repeated the experiment, only, instead of 

 leaves, I now made use of a small quantity of conferva rivu- 

 laris; when I had nearly the same result as with the leaves. 



To ascertain the relative quantities and qualities of 

 the airs yielded by the green water, when exposed with 

 fresh leaves, and when exposed with raw silk ; and also to 

 ascertain, at the same time, how long, leaves, exposed in 

 green water, retain their power of separating air. from it, 

 I made 



Experiment No. 32. 



Two equal globes, A and B (containing each 46 cubic 

 inches), the former (A) filled with green potatoe-water, 

 strained through linen, and four peach-leaves ; the latter 

 (B) filled with the same potatoe-water, strained in like 

 manner, and 17 grains of raw silk, were exposed from 

 Sunday noon, September loth, till Monday evening; 

 the weather being cold, with many flying clouds, in all 

 about 6 or 7 hours sun. 



The airs produced were as follows : 



By the globe A, with green water) Quantity. Quality. 



and 4 peach-leaves . . . . J 2 T 7 o cubic inches ' 2 9^ 'degrees. 

 By the globe B, with green water 



and 17 grs. of raw silk 



reen water ) 



r 



ilk . . .) 



