5% Analysis of the Coprolites of Birds. 



Alcohol, sp. gr. 0-832, dissolves, by cold digestion, muriate of 

 soda and a little organic coloring matter. This being evaporated 

 dry and redissolved in water, gave, by spontaneous evaporation, 

 a mass of cubic crystals, which by sulphuric acid evolved muri- 

 atic acid. They gave no trace of potash nor ammonia by mu- 

 riate of platina ; nor of ammonia by caustic potash. On treat- 

 ing the solution of these crystals in water by nitrate of silver, 

 to determine the quantity of chlorine present, the whole imme- 

 diately became milky, and by transmitted light, slightly yellow. 

 The whole soon subsided into yellow brown flocks, which were 

 followed by gray flocks. After some hours the clear solution was 

 decanted, and the flocks treated with ammonia to solve the chlo- 

 ride of silver. The whole liquor became immediately of a 

 brown color, and the flocks so minutely divided as to appear a 

 complete solution. They soon collected at the bottom, and the 

 liquor become colorless. The undissolved flocks, which I sup- 

 posed to be urate of silver, though I did not expect to find urates 

 in the alcoholic solution, were collected and treated with nitric 

 acid. Being evaporated nearly dry, began to turn yellow. I 

 found nitric acid in excess, and exposed the evaporating dish to 

 the vapor of pure ammonia ; the mass became orange red, and 

 on heating, decidedly and distinctly pinky. The clear liquor 

 — the ammoniacal solution — which had been decanted from the 

 brown flocks, seems by the excess of ammonia to have robbed 

 them of a portion of their acid, or perhaps a bi-urate had fallen ; 

 for on evaporating the solution and treating it with nitric acid, 

 a brownish and pinky residuum was left. By inverting the 

 evaporating dish over white paper, the transmitted light gave a 

 rosy hue approaching that produced on snow a few years ago by 

 the auroral light. This residuum was again treated with water, 

 and then with ammonia, which solved muriate of silver and also 

 a brown yellow matter, giving the solution the appearance of a 

 weak solution of geine. It appeared during some of these ex- 

 periments, as if the nitric acid of nitrate of silver had acted very 

 much like nitric acid and uric acid ; but this is not essential to 

 the proof of the presence of uric acid, and I omit this, merely 

 alluding to it as a fact quite novel to me, and pass on to the educts 

 by cold water from the coprolite. I had in my first trials, made 

 a number of experiments on a portion of the coprolite remaining 

 in one of my test tubes, which at the time I ran my pen through, 



