64 RESPONSE IN THE LIVING AND NON-LIVING 



ten minutes, and two records were taken during that 

 time. It was then raised by 10 C., and the same process 



FIG. 37. THE GLASS CHAMBER CONTAINING THE PLANT 



Amplitude of vibration which determines the intensity of stimulus is measured 

 by the graduated circle seen to the right. Temperature is regulated by the 

 electric heating coil K. For experiments on action of anaesthetics, vapour 

 of chloroform is blown in through the side tube. 



was repeated. It will be noticed from the record 

 (fig. 38) that in this particular case, as the temperature 



20C 



V 



1 min. 



FIG. 38. EFFECT OF TEMPERATURE ON KESPONSE 

 The response was abolished at the hot-water temperature of 55 C. 



rose from 20 C. to 30 C., there was a marked diminu- 

 tion of response. At the same time, in this case at 



