MYSTERIES OF LIFE AND MIND 



Arrhenius, Ostwald, a mechanism of the atoms, or, 

 as it has come to be called in Germany, a physical 

 chemistry, was developing. Many of Dr. Loeb's 

 experiments had been upon the effect of various 

 chemical stimuli. The new theories, which had 

 divided chemists into camps of friend and foe, 

 seemed to offer new weapons to biology. One day 

 he took up the problem of the rhythmical contrac- 

 tions of the jelly-fish, a subject dear to Romanes, 

 the protegt of Darwin. If the upper part of the 

 animal be cut away, the contractions stop. Dr. 

 Loeb tried placing the beheaded animal in a solu- 

 tion of common salt; the movements began again. 

 A bit of potassium or calcium added, they stop 

 again. 



But if this be true of a lowly jelly-fish, perhaps 

 it is equally true of the rhythmical beat of the 

 heart. And this Dr. Loeb found to be the case. 

 An excised heart could be kept beating for hours, 

 stopped, started, quickened, or slowed, simply by 

 changing slightly the chemical character of the 

 solution in which it was placed. In the same way 

 an ordinary muscle, that, for example, of a frog's 

 leg, could be made to beat in rhythm. Surely this 



- coming very near to " playing with life." The 

 whole literature of these astonishing researches 

 reads like Faust -dreams come true. If a Newton 

 could tremble before the proof that a mathematical 



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