BILIARY CONCRETIONS. 471 



contradistinction to the general rule, it contained mere traces 

 of cholesterin, and was principally composed of biliary resin, 

 and modified colouring matter. 



[Bertazzi 1 has recently announced the discovery of copper 

 as a constant ingredient of gall-stones. He analysed fourteen 

 of these concretions sent to him by Polli, and found it in every 

 instance. The amount of copper seemed to stand in a direct 

 ratio to the amount of bile-pigment in the calculus. Thus, 

 on incinerating an almost black spongy-looking concretion, so 

 large a quantity of copper was present in the ash, that an iron 

 cylinder, nearly a line in diameter and four inches long, after im- 

 mersion for a few seconds in a dilute acid solution of the residue, 

 was entirely coated. When, on the other hand, merely the 

 nucleus or the external layer contained pigment, the indications 

 of the presence of copper were comparatively slight, and he is 

 of opinion that perfectly white concretions are entirely devoid 

 of this constituent. With the view of ascertaining whether 

 copper could be detected in the bile, Bertazzi analysed the 

 fluid collected from the gall-bladders of ten persons. He could 

 not, however, detect any indications of the metal. 



The above statement respecting the presence of copper in 

 biliary calculi has been subsequently confirmed by Heller. 2 ] 



/ 



Biliary Concretions in Animals. 



Biliary concretions are very common in cattle : Gurlt never 

 observed them in horses, and only once detected a calculus of 

 this nature in a dog. The biliary concretions of cattle differ 

 considerably from those of man ; they consist for the most part 

 of biliary pigment and resin, with a little cholesterin. In 

 analysing the biliary concretions of oxen we must pursue the 

 method already described, but at the same time we must not over- 

 look the circumstance that an independent (lithofellinic) acid has 

 been noticed by Gobel as occurring in them, which is not found 

 in human biliary calculi. It is soluble in boiling alcohol and 

 crystallizes on cooling; on heating it fuses, becomes decom- 

 posed and burns. It is insoluble in acetic and hydrochloric 



1 Polli's Anriali cli Chiinica. Milan. Juglio 1845, p. 32. 



2 Archiv fur physiolog. und patholog. Chemie, vol. 2, p. 228. 



