550 CRILE— THEORY OF PROCESSES. 



would be destroyed should the water in the cells become and remain 

 saturated with acid salts, so that the essential difference of potential 

 between the nucleus and the cell body would be lost ; and that this 

 would happen unless continuity of the supply of fresh water is 

 assured. We know that life ends within a few days when the body 

 takes in no fresh water. 



We would expect that the electric impulse could reach and move 

 the muscle only if the conductivity of the conducting paths — axis 

 cylinders, spinal cord — were greater than the conductivity of the 

 brain, and the conductivity of the muscles greater than the con- 

 ductivity of the nerves. This point has been tested in 436 animals 

 and in every instance, in animals which were conscious at the time 

 of their death, the conductivity of the spinal cord was greater than 

 that of the brain ; the conductivity of the muscles was greater than 

 that of the spinal cord. 



We would expect to find that the greatest activity of the or- 

 ganism is coincident with the highest conductivity of the brain, 

 the spinal cord and the muscle. Under conditions of heightened 

 activity produced by artificially induced iodism we found the con- 

 ductivity of the brain, the spinal cord, and the muscles and of other 

 organs and tissues to be markedly increased above the normal. 

 Likewise, the immediate effect of the injection of adrenalin was an 

 increase in the conductivity of the brain. Likewise, the first effect 

 of physical injury, of emotional excitation, of the injection of toxins 

 is an immediate increase in the conductivity of the brain. Direct 

 measurements of the temperature of the brain after the injection of 

 adrenalin demonstrated increased activity evidenced by a rise in 

 temperature. Conversely, one would expect that decreased oxida- 

 tion would be attended by decreased conductivity and by decreased 

 activity of the nerve cells. We found that the temperature of the 

 brain was diminished after adrenalectomy, after hepatectomy, by 

 hemorrhage. 



In accordance with the electro-chemical theory we would expect 

 that bodily activity would be reduced by diminishing the dift'erence 

 in potential in the cells. This is evidenced by the effects of the 

 direct production of acidosis by the injection of acid, or of acidosis 

 resulting from any excessive activity such as prolonged or extreme 



