SECT. VI. ELABORATION OF OXYGENE. 



morning to the action of the sun's light in a receiver 

 containing 48 cubic inches of atmospheric air de- 

 prived of its carbonic acid. In the succeeding 

 evening its atmosphere was found to be augmented 

 by 4 -4 cubic inches, but without any accession of 

 carbonic acid ; 274- parts in the hundred being 

 oxygene, as indicated by the eudiometer, and the 

 remainder being nitrogene. Before the experiment 

 the receiver contained 10*1 cubic inches of oxygene, 

 and 3 7 '9 f nitrogene ; after the experiment it con- 

 tained 14-28 of oxygene, and 38*1 of nitrogene. 

 The amount of the difference, then, or the quantity 

 of gas extricated was 4-18 cubic inches of oxygene, 

 and O*2 of nitrogene. The experiment was con- 

 tinued with the same plant during seven successive 

 days and nights. In the course of the second night 

 the quantity of oxygene inhaled was equal to 3%- 

 <?ubic inches ; and in the course of the following day 

 the quantity of gas evolved was equal to four cubic 

 inches of oxygene, and % cubic inch of nitrogene. 

 In short it was found during the seven days of ex- 

 periment, that the quantity of oxygene alternately 

 inhaled and evolved, during the night and day, was 

 always diminishing ; and the quantity of nitrogene 

 extricated, always increasing ; the quantity of oxy- 

 gene inhaled upon the whole being 21-f- cubic inches, 

 and the quantity of gas evolved upon the whole 

 being 29^- cubic inches, of which 23^- were oxygene 

 and 6^- nitrogene. 



Saussure varied the experiment upon the extrica* 



