23 



or in circumstances where no living action is going 

 on. 



20. As therefore the carbonic acid met with in 

 germination is not emitted ready formed by the 

 seed, it must be produced exterior to it ; and for 

 this purpose carbon must be in some way furnished. 

 Dr Woodhouse supposes this carbon to proceed ei- 

 ther from the earth in which the seeds are planted, 

 from some decayed portion of the living leaves, or 

 from the cotyledons of the seed itself* ; but this 

 acid has been shown to be formed where no earth 

 is present, and before any leaves appear, (7. 8.), and 

 where the seed itself exhibits no sign of decay. It 

 is plain, therefore, that the living seed, during its 

 germination, must possess a power of supplying car- 

 bon ; and by the union of this carbon with the oxy- 

 gen gas of the air, the carbonic acid that is met with 

 must be formed. We find accordingly, that the 

 carbonic acid produced does actually exceed in 

 weight (13.) the oxygen gas that disappears; and 

 the carbon that occasions this excess can be derived 

 only from the living seed, which, if the experiments 

 of Hassenfratz are to be trusted, contains less car- 

 bon after germination than it did before it was sub- 

 mitted to that process ! 



21. But it has been said, that when the air used 

 in this process contains no oxygen gas, or when all 

 which it contained has been converted into carbo- 

 nic acid, germination no longer goes on. This can?- 



* Nicholson's Journal, July 1802, p. 151. 

 f Annales de Chirme, torn. xiii. p. 188. 

 B4 



