50 Analysis of the Coprolites of Birds. 



ash, dilute ; the clear solution neutralized exactly with muri- 

 atic acid, and then treated with muriate of hme, let fall copious 

 flocks. These solved, without a trace of a bubble escaping, in 

 dilute muriatic acid ; this last solution let fall, when it was sat- 

 urated with lime water, copious flocks. These flocks can be only 

 phosphate of lime. You will have observed all along, how ob- 

 stinately a little iron and alumina adhere to the precipitated 

 phosphate of lead and silver. Still these were separated. But 

 their amount in the lead cannot materially affect the proportion 

 of phosphate of lime I sent you. The same is true of the 

 amount of sulphate in the precipitated phosphate of lead. I pre- 

 sume these results establish the presence of phosphoric acid. 

 Still to leave no stone unturned, I had reserved all the above 

 precipitates of supposed phosphate of silver; they were solved 

 in dilute nitric acid. The silver was separated by muriatic acid, 

 and the excess of acid, then nearly neutralized by pure carbonate 

 of soda, and the following trials made with it. 



a. To the solution add pure muriate of lime, no effect ; but 

 on neutralizing with pure ammonia, a copious white precipitate, 

 easily soluble in acid, without eflervescence. 



h. The solution was rendered slightly alkaline by ammonia ; 

 became opalescent, but on the addition of sulphate of magnesia, 

 a copious precipitate. 



c. The muriate of lime used was rendered a little alkaline by 

 ammonia. There was no change ; but on adding the solution 

 of supposed phosphate of soda as above, a copious precipitate. 



d. Solution of sulphate of magnesia, dissolve in it cold, a few 

 grains of sesquicarbonate of ammonia. No change ; but on add- 

 ing some of the solution of the supposed phosphate of soda, im- 

 mediate flocks. 



e. The solution above was treated by lime-water, when co- 

 pious white flocks precipitated. Other trials also were made, 

 and triple phosphate of magnesia and ammonia formed. These 

 several precipitates of supposed phosphate of lime and of triple 

 phosphates were collected in two separate parcels, and the phos- 

 phate of lime washed, and then tried as follows : 



1st. It solves without a shade of effervescence in dilute nitric 

 acid. A portion of this solution, treated with nitrate of silver 

 and then neutralized by ammonia, gave freely a fine yellow pre- 

 cipitate. This slowly blackens in light. It has every character 

 of phosphate of silver. 



