310 Prof. Hitchcock on IchnoUthology, or Fossil Footmarks. 



Water, organic matter, urate and volatile salts of am 



monia, 



Chloride of sodium, 



Sulphates of lime and magnesia, 



Phosphate of lime and magnesia, . 



Carbonate of lime, 



Silicates, 



10.30 

 .51 

 1.75 

 39.60 

 34.77 

 13.07 



100.00 



In subsequent experiments he verified the existence of uric 

 acid, as well as of muriate of soda and of ammonia. 



For many very curious and interesting comparisons and analo- 

 gies, reference must be had to the paper in full, to appear in the 

 ensuing No. of this Journal. 



This appears to me to be a most beautiful example of the ap- 

 plication of chemistry to geology. A few ounces of a dark color- 

 ed substance are dug out of a quarry, in the sandstone of Chico- 

 pee river, and put into the hands of the chemist. Bringing to bear 

 upon it the searching power of analysis, he is conducted to the 

 very remarkable conclusion, that it is the excrement of an animal 

 dropped perhaps hundreds of thousands of years ago. But the 

 clue line leads him still farther. Detecting about half a per cent, 

 of a peculiar acid — the uric, in the coprolite, he is led to infer, 

 by fair reasoning, that it is the coprolite of birds, rather than of 

 any other animal. Nay, he goes still farther, and shows that it 

 must have been derived from a particular kind of birds, viz. the 

 omnivorous. Truly this may be called a scientific miracle — a 

 resurrection from the dead, and among the many analogous mir- 

 acles wrought in the nineteenth century I know of scarcely any 

 more marvellous than this ! 



I might add here, that if we are not mistaken in supposing the 

 coproHte to contain seeds, the fact lends confirmation to the con- 

 clusion of Dr. Dana, that it was dropped by an omnivorous, in- 

 stead of a carnivorous bird. Had it been mostly composed of 

 comminuted animal matter, as somecoprolites are, we should have 

 found some discrepancy between the fact and the results of anal- 

 ysis. But now the mechanical composition harmonizes with the 

 chemical ; and I may add, both correspond with the conclusion 

 deduced from the history of the footmarks. 



The progress of light and evidence in respect to these foot- 

 marks it is interesting to trace. When first discovered, so striking 



