SECTION XXV 

 THE INTERNAL SECRETIONS 



CHAPTER LXXXI 



THE THYROID AND PARATHYROID BODIES* THE THYMUS, 

 LIVER, AND PANCREAS 



General Discussion. ^ — The beginning of the scientific study of the 

 ductless glands dates from 1849, when Berthold^ showed that the tes- 

 ticles produce an internal agent which is transferred by them directly 

 into the blood-stream. He proved his point by removing these organs 

 from cocks and grafting them upon some other part of the body. 

 Peculiarly enough, these animals ''remained male in regard to voice, 

 reproductive instinct, fighting spirit, and growth of comb and wattles.'^ 

 In 1855, Claude Bernard^ gave a more elaborate presentation of this 

 subject by stating that glands may form a secretion externe by with- 

 drawing substances from the blood, and also a secretion interne by 

 passing their products into the blood. He illustrated this conception 

 by referring especially to the liver which, in addition to its external 

 secretion, the bile, also furnishes an internal agent which is directly 

 concerned in the aggregation of glycogen and the formation of sugar. 

 In 1889, Brown-Sequard, then 72 years of age, announced to the Society 

 de Biologie de Paris that he had carried out upon himself a series of 

 experiments with extract of testicle, proving that this therapy ''has 

 given him much physical strength, an invigoration of cerebral function, 

 and a good appetite and digestion. " Then followed a period of organo- 

 therapy during which practically every organ of the body was tested 

 as to its remedial qualities in diseases supposedly produced by a 

 deficiency of some internal secretion. Much of this material, however, 

 is absolutely valueless, because aggrandized for purposes of commercial 

 exploitation. 



Brown-Sequard has added to the conception of Bernard the idea 

 that certain glands secrete certain specific substances into the blood- 

 stream, tending to produce a definite correlation of function between 

 different organs. This interpretation of facts really forms the basis 

 of a new function. Several years later Schiff compiled additional 



^ For references see : Biedl, The Internal Secretory Organs, translated by 

 Williams, Wood & Co., 1913. 



2 Archiv fiir Anat., Physiol, und wissensch. Medizin, 1849, 42. 



3 Legons de physiol. exper., Paris, 1855. 



951 



