802 REPOKT — 1894. 



but which, so far as we know, have no physiological connection with them. Now, 

 when experiments came to be directed upon these bodies in order to elucidate their 

 functions, and especially to observe whether their injury or removal was accom- 

 panied in animals also hy symptoms similar to those occurring in man as the result 

 of disease, it was found by Brown-Sequard that when these bodies are totally 

 removed in any animal the removal is speedily followed by a fatal result. These 

 experiments of Brown-S(5quard's were made in 1858, and at the time attracted some 

 attention. They were repeated by other experimenters with similar efiects. But some 

 of those who removed the supra-renal capsules obtained contrary results, and for 

 many years the matter remained in an undecided condition. It was even supposed 

 that the fatal results which were got by Brown-S(5quard might be due to the shock 

 of the operation or to the fact that the removal necessarilj' involves certain parts of 

 the sympathetic nervous system, and were not necessarily due to the removal of the 

 eupra-renals. Recently, however, attention lias been again directed to the subject, 

 and the experiment of Brown-S(5qiiard lias been repeated by Tizzoni (1889) and 

 by Abelous and Langlois (1891 to 1804) in various animals — viz. frogs, guinea- 

 pigs, rabbits, and dogs. I have myself performed confirmatory experiments in 

 monkeys. The result of all these I'ecent observations is to show that the complete 

 removal of the supra-renal capsules is not compatible with prolonged existence of 

 life ; and Abelous and Langlois have shown that it is accompanied by an alteration 

 in the blood, which renders that fluid poisonous to other animals. The contrary 

 results which have been obtained by some investigators are apparently due to the 

 fact that in certain cases there are, as with the thyroid body, small isolated por- 

 tions of supra-renal substance (' accessory capsules,' as they are sometimes called) 

 which have not been noticed and removed at the time of the operation, and that 

 these small portions of supra-renal substance have served to maintain that proper 

 relation between the blood and the gland which is sufficient to prevent the super- 

 vention of the symptoms in question. 



Isow the weight of both supra-renal capsules taken together is not more than 

 three drachms, and their weight, as compared with that of the whole body, is only 

 as 1 to 0,000 or less. The accessory supra-renal capsules which may be left after 

 the removal of the main bodies probably do not originally weigh more than one- 

 twentieth of the whole structure, and yet this minute proportion of material (a 

 material, so far as we know, unique in the organism) is nevertheless sufficient to 

 maintain the composition of the blood and the nutritive equilibrium of the body, 

 and thus to prevent the necessarily fatal result of complete removal. 



Now it has been found in the case of the thyroid gland that patients in which 

 this structure has been so diseased that its function is seriously interfered with, and 

 animals in which it lias been removed entirely, may be greatly benefited, if not indeed 

 cured, by tlie inception, either subcutaneously or with food, of the thyroid glands 

 of animals, or of the juice of such glands. Even where no afiection of the thyroid can 

 actually be detected, the exhibition of thyroid juice is frequently beneficial in cerl ain 

 conditions of the system ; and it was noticed by Dr. Oliver, of Harrogate, that this 

 is especially the case where there is a too-marked constriction of the blood-vessels, 

 the juice of this body tending in such cases to reduce the extreme tone of the vascular 

 walls, which is the cause of this condition. Encouraged by this result, Dr. Oliver 

 was led to examine the efiects of otlier animal extracts, and among them that of 

 extract of supra-renal capsule. The efl'ect of this was precisely the reverse of that 

 which he had got with the thyroid body, for he obtained evidence tending to show 

 that in certain cases in man extract of supra-renal capsule can produce an increase 

 of vascular tone and a diminution in the size of the arteries. Beyond this point, 

 however. Dr. Oliver was unable to proceed by clinical experiment, and he accord- 

 ingly came to my laboratory with the object of determining the precise physiolo- 

 gical effect of the active substance of the capsules. The results which were obtained 

 show that there is present in both alcoholic and watery extracts of the gland a 

 most potent physiological substance which when injected into the body of an 

 animal produces, even in minute doses, a remarkable effect upon certain parts of 

 the nervous ."system, upon the muscular system, upon the heart, and upon the 

 blood-vessels. If only as much as a grain by weight of supra-renal capsule be ex- 



