196 Professor Jagadis Chunder Bose [May 21), 



serious drawback in the investigation on growth. For even with 

 the existing magnifying growth-recorders it would take many hours 

 for the variation of growth to be recorded under the given changed 

 conditions in the environment. The results thus obtained are subject 

 to errors brought about by the variation of growth which takes place 

 spontaneously in the course of a few hours. Growth can be assumed 

 to remain constant only for a short time ; on this account it is 

 necessary to conclude an experiment in the course of a few minutes. 



By means of microscopic projection it is possible to magnify 

 growth ; but such an arrangement will not be self-recording ; there 

 is again a serious error introduced by the action of strong light, 

 which profoundly modifies the rate of normal growth. 



These difficulties have been overcome in my high magnification 

 Crescograph, which records the absolute rate of growth in a time so 

 short as the single beat of the pendulum. The various magnifica- 

 tions available are a thousand or ten thousand times. For demon- 

 stration purposes I have been able to secure a magnification of a 

 million times. The infinitesimal growth thus becomes magnified so 

 as to appear rushing forward as if in a race. The actual rate of 

 growth and its variations under the action of drugs, of food -materials, 

 of various electrical and other forms of stimuli, are thus recorded in 

 the course of a few minutes. The great importance of this method 

 of investigation in agriculture is sufficiently obvious. 



The plant has thus been made to exhibit many of the activities 

 which we have been accustomed to associate only with animal life. 

 In the one case, as in the other, stimulus of any kind will induce a 

 responsive thrill. There are rhythmic tissues in the plant which, 

 Hke those in- the animal, go on throbbing ceaselessly. These spon- 

 taneous .pulsations in tlie one case, as in the other, are affected by 

 various drugs in an identical manner. And in the one case, as in 

 the other, the tremor of excitation is transmitted with a definite and 

 measured speed from point to point along conducting channels. The 

 establishment of this similarity of responsive actions ii the plant 

 and animal will be found of the highest significance ; for we now 

 realize that it is by the study of the simpler phenomena of irritability 

 in the vegetal organisms that we may expect to elucidate the more 

 complex physiological reactions of the animal. 



The Plant's Response to the Shock of Death. 



A time comes when, after an answer to a supreme shock, there is 

 a sudden end of the plant's power to give any further response. 

 This supreme shock is the shock of death. Even in this crisis there 

 is no immediate change in the placid appearance of the plant. 

 Drooping and withering are events that occur long after death itself. 

 How does the plant, then, give this last answer ? In man, at the 



