276 Proceedings of the Royal Irish Academy. 



1. That an easy and reliable qualitative test of the presence of the 

 colouring matter of bile in the urine is afforded by placing a dmm. 

 stratum of the suspected fluid before the slit of the spectroscope, and 

 observing whether the special absorption, which I have described, 

 takes place. 



2. That no other normal or abnormal constituent of the urine 

 affords this special absorption. 



3. That to so examine such suspected urine, by the bedside of the 

 patient, with one of the small but effectual spectroscopes, which are 

 now so constructed as to be easily carried in the waistcoat pocket, is a 

 procedure as quick and easy as Gmelin's test, and quicker and easier 

 than Pettenkoffer's. 1 believe it to be more reliable than either. 



4. That the daily increase or decrease of the absorption (in the 

 same individual) is capable of approximately indicating the increase 

 or decrease of the biliary colouring matter in the urine ; and, pro tanto, 

 the extent of the excretion of bile through that channel. 



5. That this test affords an additional proof of the present physio- 

 logical opinion, that biHary colouring matter is a haemoglobin disinte- 

 gration derivative. 



Demonstrations of the various spectra described were given. 



KOTE ADDED IjS^ THE PRESS. 



Since the reading of this Paper Dr. Charles A. MacMunn's new 

 work, "The Spectroscope in Medicine," has come to hand. This 

 volume abounds in original research, and contains information of the 

 most valuable and practical kind ; it does not, however, describe this 

 particular test for bile. 



At the suggestion of Dr. G. Sigerson, M.R.I. A., the author has 

 tried whether the acidity or alkalinity of the icteric urine altered its 

 peculiar absorptive power ; and he finds that it does not. 



