238 LIFE AND WORK OF SIR JAGADIS C. BOSE 



the plant itself. This evidence of the plant's own script 

 removed the long-standing error which divided the vegetable 

 world into sensitive and insensitive. The remarkable 

 performance of the ' Praying ' Palm Tree of Faridpore, which 

 bows, as if to prostrate itself, every evening, is only one of 

 the latest instances which show that the supposed insensi- 

 bility of plants and still more of rigid trees is to be ascribed 

 to wrong theory and defective observation. My investi- 

 gations show that all plants, even the trees, are fully 

 alive to changes of environment ; they respond visibly 

 to all stimuli, even to the slight fluctuations of light caused 

 by a drifting cloud. This series of investigations has 

 completely established the fundamental unity of life- 

 reactions in plant and animal, as seen in a similar periodic 

 insensibility in both, corresponding to what we call sleep 

 as seen in the death-spasm, which takes place in the plant 

 as in the animal. This unity in organic life is also exhibited 

 in that spontaneous pulsation which in the animal is heart 

 beat ; it appears in the identical effects of stimulants, 

 anaesthetics and of poisons in vegetable and animal tissues. 

 This physiological identity in the effect of drugs is regarded 

 by leading physicians as of great significance in the scientific 

 advance of Medicine ; since here we have a means of testing 

 the effect of drugs under conditions far simpler than those 

 presented by the patient, far subtler too, as well as more 

 humane than those of experiments on animals. 



Growth of plants and its variations under different 

 treatment is instantly recorded by my Crescograph. 

 Authorities expect this method of investigation will advance 

 practical agriculture ; since for the first time we are able 

 to analyse and study separately the conditions which 

 modify the rate of growth. Experiments which would 

 have taken months, their results vitiated by unknown 

 changes, can now be carried out in a few minutes. 



Returning to pure science, no phenomena in plant-life 

 are so extremely varied or have yet been more incapable 

 of generalisation than the ' tropic ' movements, such as 



