68 



without injury to the par vagum, there is seen to be a control 

 over the action of the heart during insj)iration. But if the par 

 vagum of both sides of tlie chest be cut across, this control is 

 lost. There is good ground for belief, therefore, that at every 

 effort of inspiration, there is a transmission of nervous influence 

 along the par vagum to the heart, acting as a check upon it and 

 regulating its action, and thus preventing the increase of pulsa- 

 tion, which might otherwise go on, in increased ratio to infinity, 

 under the excitement of forced respiration. 



It has been said that people liave killed themselves by stopping 

 the heart's action. One of the brothers Webber, of Leipsic, 

 found that when an effort was made to contract the chest during 

 a full inspiration, that there was great suffering, fainting, and 

 almost death. Webber himself nearly lost his life trying the 

 experiment. By irritating the various organs which receive 

 branches from the par vagum, as the stomacii, spleen, &c., by 

 galvanizing them or crushing them at once by a blow of a ham- 

 mer upon an iron surface, it is found that the heart's action is 

 diminished in frequency, and in some instances entirely sus- 

 pended. Cases of sudden death from a blow upon the stomach 

 externally are to be attributed to the same cause. The action 

 upon the heart from overloading the stomach, either with too 

 much solid or liquid matter, is to be explained also by the influ- 

 ence of the par vagum upon the heart. 



Dr. Sequard also referred briefly to his researches upon the 

 Supra-renal Capsules. These two small organs, lying in imme- 

 diate connection with the kidneys, have been considered very 

 unimportant until within a few years. Now it is found that, 

 when they are removed from the body of a living animal, there 

 occurs a very great change in the blood, and the animal dies in a 

 short time,— sooner even than after the removal of the kidneys. 

 There is found also to be an accumulation of pigment and a 

 peculiar form of crystals, (not having the chemical reactions of 

 htematoidine.) in the blood. 



Dr. Gould called attention to the remarks of M. Sequard as 

 interesting in a pathological point of view. He had recently 

 attended a case of what he regarded as " bronzing of the skin," a 

 disease lately recognized and described by Dr. Addison, of Lon- 

 don, who has found in cases of '■'■bronzed skin" an alteration of 



