NEW CONCEPTIONS IN SCIENCE 



mor's hypothesis of electrons, which supposes a 

 kind of an electric atom, a charge not associated 

 with ordinary matter, he believes that, for ex- 

 ample, the electron rotates about the atom of flu- 

 orine twice as fast as about the chlorine atom, and 

 hence develops a more powerful field of action. 



But all this is merely mathematical speculation. 

 It is interesting, but not proved. Still, the general 

 theory does link together, apparently, a wide num- 

 ber of related facts. Heat, for example, would 

 make the colloid solution thinner, hence the nerve 

 would be less easily stimulated than when cold. At 

 high temperature the colloids would turn into jelly, 

 and the nerve be excited. So the excess of negative 

 ions, speeding along the nerve, would explain what 

 physiologists call negative variation. There are 

 other matters of much too technical a nature to be 

 entered on here the effect of the different kinds of 

 light and the like. 



To sum it up, Professor Mathews's theory is that 

 what happens to a nerve when it is excited is noth- 

 ing less than a tendency to "jell," just as happens 

 to the housewife's jams and custards when they 

 are left to cool. And this effect depends on four 

 factors : 



i. The kind of electricity, negative or positive, 

 carried on the colloid particles of the nerve, and by 

 the atoms in the solution which surround them ; 



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