310 
DR. HASSAUL ON THE PRESENCE OF INDIGO IN HUMAN URINE. 
the elimination of excess of carbon from the system ; this view is confirmed by the 
nature of the cases in which indigo has been met with in the largest quantities in 
human urine, namely in cases of phthisis involving extensive pulmonary disease, and 
in cholera. 
7th. There appears strong reason for believing that the blue pigments, cyanourine 
and uroglaucin, if not identical with, are but states or modifications of indigo, since 
they resemble that substance in many of their chemical and physiological relations, 
and in their ultimate composition. 
