16 



with a little more than four of oxygen, and conse- 

 quently .that the proportion of carbon was only 

 l-5th of th'e compound*. Hence, therefore, if 

 these experiments and calculations be correct, the 

 quantity of carbon, which enters into the carbonic 

 acid formed by germination, is rather greater than 

 the experiments of Guy ton assign as the proportion 

 of that substance which forms this acid in combus- 

 tion. 



34. M. Huber made experiments with the view 

 of ascertaining the composition of the atmosphere 

 best suited to carry on the germinating process. 

 He found, that an artificial atmosphere, composed 

 of the same constituent parts as common air, favour- 

 ed it precisely in the same manner ; that germina- 

 tion was retarded in proportion as the nitrogen gas 

 exceeded the usual quantity of that gas contained in 

 atmospheric air, but was little affected when the va- 

 riation was small. A superabundance of oxygen 

 gas also, although not destructive to germination, 

 nevertheless retarded the process ; for seeds were 

 found to germinate better in a mixture formed of 

 three parts nitrogen and one of oxygen, than in one 

 composed of three of oxygen mixed with one of ni- 

 trogen f. Hydrogen gas, in the course of these ex- 

 periments, was often substituted for nitrogen, and 

 answered precisely the same uses, germination be- 

 ing more vigorous in proportion as the hydrogen 

 came near to that of the nitrogen existing in the at-* 



* Annales de Chimie, torn. xxxi. p. 108. 



f Sur la Germination, p. 31. ct secj. 



