OF MUSCULAR MOTION. 197 



muscles to be impaired ; they would doubtless contract immedi- 

 ately after this experiment, upon the application of a stimulus, as 

 readily as they do after apoplexy. The ligatures act immediately 

 by depriving the nerves of the power of stimulating them j for 

 a supply of arterial blood is necessary to the function of the 

 nervous system,* and the ligature of the abdominal aorta cuts 

 this off from the lower part of the spinal marrow and what 

 originate from it, the nerves of the hind legs. If venous blood 

 is sent to the brain, death ensues, and the function of any part 

 is arrested by forcing venous blood into its arteries. f 



Another source of paralysis must ultimately arise, the loss 

 of irritability from the want of circulation in the muscle. 



* Le Gallois, Sur le Principe de la Vie. 

 t Uicliat, Kcchffches Pliyeiologi^ues, 



