174 



rer imbibed is constantly escaping from the seed, 

 there is reason to believe, that it is the proper men- 

 struum and vehicle of this carbon. Hence, in the 

 foregoing experiments of M. Huber (133-4.), the 

 carbon furnished by the seed united first with the 

 oxygen gas, until that gas became saturated, and af- 

 terwards combined with the nitrogen or hydrogen, 

 whose affinity for it is not so strong as that of oxy-.. 

 gen *. Even after combining with hydrogen, car- 

 bon will again leave it to unite with oxygen, either 

 when the two gases are inflamed together by electri- 

 city, or are suffered for a few hours to remain at 

 rest. If, however, fresh portions of oxygen be suc- 

 cessively supplied, the carbon, afforded by the seed, 

 seems to unite with it alone, and germination regu- 

 larly proceeds. There does not, in these examples, 

 appear to be any ground for supposing the oxygen 

 gas to be first received into the seed in order to 

 combine with its carbon, and to be afterwards ex- 

 pelled from it in the form of carbonic acid ; for no 

 known powers of the seed are capable of performing 

 such an office, and such a supposition is the less ne- 

 cessary, since the seed is able to emit carbon with- 

 out it. If also, from the mere fact of their combi- 

 nation, the oxygen gas be considered to enter into 

 the seed, and abstract its carbon, the hydrogen gas 

 must be held to do the same ; and the same thing 

 may likewise be affirmed of nitrogen gas, with 

 wkich (133.) the carbon of the seed will combine. 

 Moreover, the seed affords carbon through every 



* Murray's System of Chemistry, vol. ii. p. 311. 



