36 STUDIES ON FKUIT EESPIBATION. 



The same data are given graphically in figures 16 and 17 (pp. 37 and 

 38) . The curves and model show that fruits stored under such condi- 

 tions increase in temperature and in physiological activity more or 

 less rapidly according as they are warm or cool when adiabatic con- 

 ditions are imposed. At cold storage or refrigerator temperatures. 

 in case of the example given, the temperature rose 0.3° and 0.7°, 

 respectively, during 10 hours, whereas during the same interval the 

 temperature rose 1.45° and 3.65° when the temperatures at which the 

 fruit was stored were 20° and 30° C, respectively. It has been sug- 

 gested that it would be possible to foUow the rate of temperature 

 rise of a product about to undergo self-heating by placing a recording 

 thermometer near the center of the material. If the heating observed 

 was due to the operation of the respiratory activities alone, it is 

 probable that the curve drawn by the recording thermometer would 

 approximate the theoretical curve which could be drawn in advance 

 from a knowledge of the respiratory activity. It is thus highly 

 probable that this method of calculating the temperature rise and of 

 tracing the theoretical curve will be of value in the investigation of 

 phenomena of self-heating, the causes and mechanism of which are 

 now but little understood. 



