956 EXPERIMENTS OF BRODIE AND PHILIP. 



fear or grief, the brain be inordinately excited, 

 so as to send forth a stimulus vitiated in quality, 

 the stomach, which receives it, will partake of 

 the disorder, causing the loathing or sickness so 

 often induced by unexpected bad news." (Prin- 

 ciples of Physiology, p. 279.) 



Many others maintain with Bichat and Riche- 

 rand, that the organs of digestion, circulation, 

 secretion, &c. are supplied with vital energy by 

 the ganglionic system of nerves. But I have 

 demonstrated in a preceding chapter, that so 

 far as respiration depends on the voluntary action 

 of the brain and medulla oblongata, (exerted 

 chiefly through the nervus vagus?) they are essen- 

 tial to the evolution of caloric in the lungs, san- 

 guification, secretion, nutrition, and growth ; but 

 no further. Hence it is, that division of the 

 vagus of rabbits causes impeded respiration, a 

 reduction of temperature, and indigestion, as in 

 the experiments of Dr. Philip ; while other physio- 

 logists have found that it destroys life in a few 

 days. But it was found by Sir Benjamin Brodie, 

 that when the vagus was divided in young cats, 

 near the cardia of the stomach, and below the 

 branch distributed to the lungs, the conversion of 

 food into chyme and chyle was not prevented. 



When the mind is overwhelmed with anxiety, 

 grief, despair, or some all absorbing passion, it 

 is no longer capable of exercising its accustomed 

 voluntary power over respiration, on the due 



