Analysis of the Coprolites of Birds. A9 



No. 1, was slowly treated, cold, in pure nitric acid — ^the solution 

 decanted and treated with nitrate of silver. On neutralizing the 

 pure acid, a dirty yellow fell. The ammonia in excess, a copious 

 gelatinous precipitate fell, which was digested some hours, cold, 

 in acetic acid. Nitrate of silver produced in this a copious bright 

 yellow, which subsided rapidly and blackened in the sun. The 

 digestion with acetic acid was several times repeated. The mass 

 insoluble in acetic acid, was then treated with warm dilute caus- 

 tic potash, which solved traces of alumina, which was detected 

 by the usual mode ; while the alkali itself became partly con- 

 verted into phosphate of potash, which was evident by its solu- 

 tion, (neutralizing by muriatic acid,) precipitating muriate of 

 lime. The mass all solved by acetic acid and by potash, was 

 then examined and found to consist of iron, lime, and phosphoric 

 acid ; which last was converted into phosphate of silver with its 

 usual decided characters. 



No. 2. I could not suppose that my examination of this for 

 uric acid had decomposed the phosphates. I examined it as 

 above, and again found phosphoric acid. The great bulk of No. 

 2, however, I submitted to the latest test proposed by Liebig, for 

 earthy phosphates. It was solved in muriatic acid, the solution 

 treated with perchloride of iron, and the whole precipitated by 

 ammonia. The precipitate was then digested with sulphuret of 

 ammonium. The phosphoric acid if present, would be now con- 

 verted into phosphate of ammonia; on adding sulphate of mag- 

 nesia to this, a triple phosphate precipitated. In order to be sure 

 of this, the triple phosphate was examined and converted readily 

 into phosphate of silver. 



No. 3. The precipitated phosphate of silver was now examined. 

 It proved to be such, and will be further noticed after No. 4. 



No. 4. Phosphate of lead, from which I had deduced the 

 quantity of phosphoric acid. It solved in dilute nitric acid with- 

 out effervescence ; wholly soluble, with the exception of a very 

 minute portion, a dirty gray looking white. The solution was 

 treated by sulphuric acid. After the sulphate of lead had sub- 

 sided, the clear solution, decanted, was found to contain traces 

 both of iron and alumina ; these being separated, the solution 

 readily aiforded, with magnesia, triple phosphate. Another por- 

 tion, decanted from the sulphate of lead, was also treated by 

 excess of ammonia. The precipitate boiled with caustic pot- 



Vol. xLviii, No. 1.— Oct.-Dec. 1844. 7 



