360 MODE OF PEODUCTION OF JAUNDICE. [BOOK II. 



one case seventeen days elapsed between the date of the application 

 of the ligatures and that on which the animal was killed. It, there- 

 fore, appears to be proved, beyond the possibility of doubt, that it is 

 only through lymphatic paths that the biliary constituents can leave 

 the liver and enter the blood. The bile colouring matter first makes 

 its appearance in the urine, and if the quantity entering the blood 

 cannot pari p'assu be excreted by the kidneys, it is deposited in, and 

 stains, in the first instance, the conjunctive, afterwards the skin and 

 other tissues. 



Although the specific constituents of the bile cannot, in the normal 

 condition, be detected in the blood, there can be little doubt that the fact is 

 due not to their complete absence (seeing that one and probably both find 

 their way normally, in minute quantities, into the lymph of the thoracic 

 duct) but to their amount being too small to admit of detection. 



Tappeiner 1 , though unable to detect bile acids in the blood of dogs, 

 was able to separate them from the lymph of the thoracic duct and to 

 identify them. Hammarsten (see p. 315) has shewn that bilirubin is a 

 normal constituent of horse's blood. Unless the quantity either of bile 

 acids or bile colouring matters becomes too large, they are, however, 

 excreted by the liver and do not occur, even in traces, in the urine. 



Having, in the above sentences, briefly summarized the results 

 of modern inquiry, as to the mode of production of jaundice, it is 

 necessary to refer to, and to discuss in some detail, the grounds upon 

 which certain views, which until lately obtained very general support, 

 have fallen into discredit, or rather have been proved to be false. 



Until comparatively recent times, knowledge as to the mode of 

 origin of the bile colouring matter and bile acids was so wanting in 

 precision that, as a necessary consequence, the mechanism of jaundice 

 was entirely misunderstood. By a great majority of physiologists 

 and physicians, notably by our own Glisson 2 , the liver was looked 

 upon as a mere filtering apparatus (colatorium) for the removal of the 

 bile which existed preformed in the blood. As, however, pathological 

 anatomy came to be more and more studied, it could not escape the 

 observations of such men as Morgagni 3 , Boerhaave and his learned 

 commentator van Swieten 4 , that many cases of jaundice exist which 

 are obviously caused by a mechanical obstruction to the flow of bile 

 into the duodenum, as by calculi and morbid growths obstructing, or 



1 H. Tappeiner, 'Ueber die Aufsaugung der gallensauren Alkalien im Dunndarme/ 

 Sitzungsber. d. Wiener Acad. d. Wissenschaft. Vol. LXXVII. (1878), Abth. in. 



2 Fr. Glissonii in inclyta Cantabrigiensi Academia Medicinae Professoris Anatomia 

 Hepatis. Hagae-Comitis. Apud Arnoldum Leers. Anno 1681... 'Verum si hepar 



spectemus dicendum profecto fuerit hepar in eum finem a natura institution esse, ut 



sanguinem a bile defaecatum reddat' (p. 411). 



3 Morgagni, De sedibus et causis morborum. 



4 Ger. L. B. van Swieten, Commentaria in Hermanni Boerhaavi Aphorismos de 

 cognoscendis et curandis morbis. Tomus in. Lugd. Batav. MDCCLIII. ' Semper autem 

 supponit (icterus) vel impeditam secretionem bilis a sanguine venae portarum, vel 



impedimentum tollens liberum exitum bilis secretae in intestinum duodenum 



Verum ingens varietas icteri est ratione causae, quae secretionem bin's vel ejus liberum 

 exitum in duodenum impedit ' (p. 127). 



