282 CRILE— THE KINETIC SYSTEM. [April 22, 



We have thus far considered the normal roles played by the brain, 

 the suprarenals, the liver, the muscles and the thyroid in transform- 

 ing latent into kinetic energy in the form of heat and motion as an 

 adaptive response to environmental stimuli. 



The argument may be strengthened, however, by the discussion 

 of the effect of the impairment of any of these links in the kinetic 

 chain upon the conversion of latent into kinetic energy. 



Effect Upon the Output of Energy of Impaired or Lost Func- 

 tion OF Each of the Several Links in the 

 Kinetic Chain. 



1. The Brain: Cerebral softening. — In cerebral softening we 

 may find all the organs of the body comparatively healthy excepting 

 the brain. As the brain is physically impaired it cannot normally 

 stimulate other organs to the conversion of latent energy into heat 

 or into motion, but on the contrary in these cases we find feeble mus- 

 cular and intellectual power. I believe also we find that in patients 

 with cerebral softening, infections such as pneumonia show a lower 

 temperature range than in patients whose brains are normal. 



2. The Suprarenals. — In such destructive lesions of the supra- 

 renal glands as Addison's disease one of the cardinal symptoms is a 

 subnormal temperature and impaired muscular power. Animals upon 

 whom double adrenalectomy has been performed show a striking 

 fall in temperature, muscular weakness — after adrenalectomy the 

 animal may not be able to stand even — and progressive chromato- 

 lysis. The significance of the last will be pointed out later. 



3. The Liver. — When the function of the liver is impaired by 

 tumors, cirrhosis, or degeneration of the liver itself, then the entire 

 energy of the body is correspondingly diminished. This diminution 

 of energy is evidenced by muscular and mental weakness, by dimin- 

 ished response and by a gradual loss of efficiency which finally 

 reaches the state of asthenia. 



4. The Muscles. — It has been observed clinically that if the 

 muscles are impaired by long disuse, or by a disease such as myas- 

 thenia gravis, then the range of production of both heat and motion 

 is below normal. This is in agreement with the experimental find- 

 ings that anesthetics, curare, or any break in the muscle-brain con- 

 nection causes diminished muscular and heat production. 



