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to abstract its carbon ; for carbonic acid was formed 

 by seeds where none of that gas previously existed. 

 From the following facts, it will be seen also, that 

 the seed, during its germination, is able to yield car- 

 bon, without the supposed agency of oxygen gas to 

 abstract it. M. Huber observed that seeds did 

 not germinate in air, which had been previously in- 

 jured by the respiration of bees, although a quanti- 

 ty of oxygen gas was added to it sufficient to carry 

 on germination, if mixed with pure nitrogen gas : 

 at first, he attributed this failure to the presence of 

 the carbonic acid which remained in the residual 

 air, but when he carefully removed this acid by 

 first washing the residual air in lime-water, he still 

 found, that although fresh portions of oxygen were 

 added, no germination took place, until after a very 

 considerable quantity of that gas had been supplied. 

 He found precisely the same thing to happen when 

 he employed the residual air that had served for 

 successive germinations, since fresh seeds would not 

 grow in such air until it was mixed with a quantity 

 of oxygen much more than sufficient to carry on 

 germination in pure nitrogen gas. Reflecting on 

 these circumstances, he conceived, that as seeds yield 

 carbon to unite with the oxygen gas of the air du- 

 ring their germination, that substance might also com- 

 bine with its nitrogenous portion : and when thus sa- 

 turated with carbon, the nitrogen might not favour 

 germination if mixed only with its usual quanti- 

 ty of oxygen, because the oxygen gas, having a 

 greater affinity for carbon than the nitrogen, would 

 carry it off from the latter to form carbonic acid, 

 and consequently not leave sufficient oxygen to sup- 



