RESPONSE IN THE LIVING AND NON-LIVING 95 



narcotics and poisons. On application of chloroform, plant 

 response disappeared, just as it does for the animal ; and 

 with timely blowing off of the narcotic vapour by fresh 

 air, the plant too revived, and 

 recovered to respond anew. 

 Poison was applied to a fresh 

 specimen, and as it absorbed the 

 poison it exhibited a modification 

 of the curve of response extra- 

 ordinarily similar to that of the 

 dying muscle ; and for the plant 

 as for the animal, response came 

 to an end altogether an appar- 

 ently clear indication of death. 

 Various drugs, poisonous in 

 quantity, were found to act as 

 stimulants when given in minute 

 doses. 



Now here comes in the value 

 of a fresh mind, untrammelled 

 by the customary prepossessions 

 of the biologist. Neither bot- 

 anist, zoologist, nor physiologist 

 had ever thought or from his 

 outlook would be likely to 

 think of attempting to poison 

 a metal : he would have con- 

 sidered the very idea of such 

 an experiment absurd. But here 



the physicist, unburdened by biological tradition, and ruth- 

 less in his logic from previous experiences of unexpected 

 correspondence, made all these experiments, and on a 

 whole series of metals. Tin, zinc, brass, and even platinum, 

 were alike dosed in succession with various poisons ; with 

 the startling results of curves of response similar to 

 those of the poisoned plants and animals, and like 



FIG. 5. Action of poison in 

 abolishing response of 

 muscle (uppermost 

 record), plant (middle 

 record), and metal (lowest 

 record). 



