209 



fallen under our examination ; and since, from what 

 has just been stated, the specific caloric of this acid 

 is found to be very little more than one-third of that 

 which the oxygen gas itself previously contained, it 

 necessarily follows, that a large quantity of caloric 

 is liberated whenever this conversion of gases takes 

 place. For this office it appears, from the observa- 

 tions of Berthollet, that oxygen gas is peculiarly 

 fitted, since no other substance gives out so much 

 caloric by the changes of constitution which it suf- 

 fers : and its powers, in the particular instance of 

 change which we are now considering, may perhaps 

 be still farther aided by the degree of condensation 

 which we have seen it in all cases to undergo. Let 

 us then inquire, w r hether the presence of caloric be 

 manifest in the several living processes above men- 

 tioned, and how far it may be deemed to arise from 

 the changes effected on the oxygenous portion of 

 the air ; and first of all in the instance of germina- 

 tion. 



167. Some peas, which had been steeped in water 

 36 hours, were placed in a small glass-jar standing 

 in a room at temperature 63. In this situation they 

 remained till signs of germination appeared, when 

 the bulb of a very delicate thermometer was plun- 

 ged into the midst of them, which had previously 

 been compared with another standing beside it. The 

 standard thermometer continued stationary for more 

 than an hour ; but the one that was plunged among 

 the peas, although at first 0.4 below the former, 

 rose in 20 minutes O.2 above it, and, in 4O minutes, 

 was 0.4 above it ; but at the end of half an hour 

 more, it had again fallen to 0.2 of superiority only, 



O 



