THERMOCRESCENT CURVE 



39 



The Thermocrescent Curve 



I was desirous of devising a method by which an auto- 

 matic and continuous curve could be obtained recording 

 the rate of growth between 22° and 40° C. The entire 

 record had to be completed within the short period of 

 18 minutes, at a rate of rise of temperature of 1° C. per 

 minute. Previous experiments, as already stated, showed 



22= 



30' 



40*- 



Q^nvfve/t^itiJinjc. 



Fig. 16. The Thermocrescent Curve. 



Ordinate represents increment of growth ; abscissa, increment 



of temperature. 



that at this rate of continuous rise of temperature there is 

 practically no lag in the plant assuming the temperature 

 of the bath, especially when it is a thin specimen. 



Experiment 13. — The specimen employed was Kysoor, 

 in which arrest of growth occurred at the minimum tempera- 

 ture of 22° C. The temperature was now raised at the 

 uniform rate of 1° C. per minute. The curve of growth was 

 taken on a moving plate which travelled at the rate of 



