CHAP. I. 



OP THE CHANGES INDUCED ON THE A.IR 

 BY THE GERMINATION OF SEEDS. 



i. IT is a well-known fact, that dried seeds, 

 although exposed to heat and air, may be kept for a 

 great length of time without undergoing any sensi- 

 ble change ; nor do they in that state, as we found 

 by experiment, in the least degree affect the air in 

 contact with them. If, however, moisture have ac- 

 cess to them, they presently begin to swell, which is 

 the first step towards their evolution. This hap- 

 pens whether they be placed in water containing air, 

 or in that which has been previously deprived of its 

 air by long boiling ; for equal numbers of the same 

 peas, at the temperature of 60 Fahrenheit, being put 

 into separate phials of fresh and of boiled water, and 

 then corked and sealed, exhibited the same appear* 

 ances, and made a like progress. In a few hours 

 the seeds in both phials were much enlarged, and by 

 the next day greatly swollen : the radicles of many 



A 



