THE BALANCED CRESCOGRAPH. 267 



Effect of Ghluroform: Exper-iment 102. — The effect of 

 chloroform vapour is relatively more depressing than 

 ether. Application of chloroform is seen to induce at 

 first an acceleration which persisted for 50 seconds, but 

 after this depression set in (Fig. 97b). Prolonged applica- 

 tion of the anaesthetic is followed by the death of the 

 plant. 



SUMMARY. 



In the Method of Balance the movement of growth 

 upwards is compensated by an equal movement of the 

 plant downwards, with the result that the record remains 

 horizontal. 



The effect of an external agent is immediately de- 

 tected by the upsetting of the l)alance, up-record repre- 

 senting acceleration above normal, a down-record the opposite 

 effect of depression below the normal rate. 



The latent period and the after-effect of stimulus may 

 thus be obtained with the highest accuracy. 



The sensitiveness of the Method of Balance may be 

 raised so as to indicate a variation of rate of growth 

 smaller than i oVo millionth of an inch per second. 



