46 Analysis of the Coprolites of Birds. 



Art. V. — Analysis of Coprolites from the New Red Sandstone 

 formation of New England ; by Samuel L. Dana, M. D. — 

 with remarks by Prof. Hitchcock.* 



Lowell, September 22, 1843. 

 Prof. Hitchcock, — 



Dear Sir — I received a few days ago the sample of supposed 

 coprolite. I set about its analysis immediately, feeling no small 

 interest in the results. I send you those at which I have arrived. 

 The quantity however which I received, was too small to allow 

 me to verify some of the results by repetition, which I shall do 

 when I may have another sample. 



Water, organic matter, urate, and volatile salts 

 of ammonia, _ _ _ 



Chloride of sodium, - - - 



Sulphates of lime and magnesia. 



Phosphate of lime and magnesia, 



Carbonate of lime, - - - 



Silicates, _ _ _ _ 



100- 

 These results authorize the conclusion, that this substance is 

 coprolite. The evidence of the existence of urate of ammonia 

 is not as satisfactory as one could wish. It is this, — 



1. Removing the muriates by alcohol, the insoluble mass was 

 largely digested in water. This last was treated by nitrate of 

 silver, which produced general turbidness ; which was follovved 

 by a purple red precipitate, which remained unchanged in color 

 for twenty four hours. This precipitate healed in a platina 

 spoon did not melt, but left a filmy scoria, which, under a mag- 

 nifier, appeared to contain metallic globules — doubtless reduced 

 silver. These characters belong to urate of ammonia. 



2. Having treated another portion with alcohol, it was then 

 boiled with water; the solution evaporated, before it became dry, 

 distinct globules of yellowish liquor collected around the upper 

 edge of the evaporating dish, and pushing the operation to dry- 

 ness, a yellow crust remained, which solved with effervescence 



* The letters of Dr. Dana formed part of the Report on Fossil Footmarks by- 

 Prof Hitchcock, to be found in Vol. xlvii, p. 292; but for want of room their pub- 

 lication was postponed to the present time. 



