272 Proceedings of the Royal Irish Academy. 



XLY. — The Application of Specthitm Analysis to the estimation- 

 OF Bile in the Eenal Seceetion of Patients suffering feom 

 Jaundice. Br F. J. B. Quinlan, M.D., Univ. Duel., Fellow of 

 THK King and Queen's College of Physicians, and Physician to 

 St. Yincent's Hospital. 



[Eead, January 26, 1880.] 



Foe some time past efforts have been made by physicians and physiolo- 

 gists to introduce into their respective branches tests and measures of 

 precision, in lieu of the vague and approximate observations of the 

 unaided senses ; and this movement has led to excellent results. The 

 action of the heart is now recorded graphically by the sphygmograph ; 

 respiration is similarly delineated ; the rapidity of the circulation is 

 exactly measured ; and albumen or diabetic sugar (existing as ab- 

 normal constituents of the urine) are expeditiously and accurately 

 estimated by the Jellett saceharimeter — which is by far the best of this 

 class of instruments. I am permitted by the kindness of your Council 

 to submit to your consideration what appears to me to be a contribu- 

 tion to this movement in the form of a simple and effectual test for 

 detecting the presence of bile (or, at least, its colouring matter) in the 

 urine of patients suffering from Jaundice ; and of approximately esti- 

 mating its increase or decrease (according as the patient gets better or 

 worse) in the same individual. I say " approximately in the same 

 individual," for the bile is not a secretion of definite strength. About 

 two^ pounds of it are secreted daily in an ordinary healthy person ; but 

 its quality varies, not only in different persons, but in the same person 

 at different times. For this reason we cannot establish an absolutely 

 quantitative formula ; but we are certainly able to watch the increase 

 or decrease of the colouring matter in the urine of the same jaundiced 

 patient. The qualitative tests at present most employed in medical 

 practice are those of Gmelin and of Pettenkoffer ; but neither are 

 perfectly reliable. In Gmelin' s test a drop of nitric acid is let fall 

 on a thin layer of the suspected urine, which has been allowed to flow 

 upon a white plate ; and if bile be present an iridescence is produced, 

 beginning with green, and running into blue, violet, red, and yellow ; 

 but this will also occur in the presence of the indigo^ forming matter 

 occasionally found in the urine as a concomitant of carcinomatous disease 

 and diseases of mal-nutrition. In Pettenkoffer' s method a peculiar 

 violet brown colour is developed by the action of sulphuric acid and 

 cane sugar upon urine containing bile ; but even here there are sources 

 of error in connexion with the presence of albumen, turpentine, or 



1 Burdon Saunderson, 1879. 



2 This used to be supposed to be identical with the vegetable indigo principle 

 Inclican; but Hoppe Sevier has shown that it is rather different. It is derived 

 from Indol [CsHvN], and its formula is CsHeN SO4 K. The defect in Gmelin's 

 test has been described by Carter, and more recently by W. G. Smith. 



