126 Mr Audubon on the Ohio. 



taking. Our Irvings and our Coopers have proved themselves 

 fully competent for the task. It has more probably been be- 

 cause the changes have succeeded each other with such rapidity 

 as almost to rival the movements of the pen. However, it is 

 not too late yet ; and I sincerely hope that either or both of 

 them will ere long furnish the generations to come with those 

 delightful descriptions, which they are so well qualified to give, 

 of the original state of a country that has been so rapidly forced 

 to change her form and attire, under the influence of increasing 

 population. Yes ; I hope to read, ere I close my earthly career, 

 accounts from those delightful writers of the progress of civili- 

 zation in our western country. They will speak of the Clarks, 

 the Croghans, the Boons, and many other men of great and 

 daring enterprise. They will analyze, as it were, into each com- 

 ponent part, the country as it once existed, and will render the 

 picture, as it ought to be, immortal. 



On the Guano or Modern Coprolite, 



I HERE are districts in England, of many miles in extent, 

 where strata of considerable thickness occur, in which one-fourth 

 part of the whole mass is made up of the foecal matter, or excre- 

 ment, of the former inhabitants of the ocean. This fact is cer- 

 tainly astonishing, but loses all its incredibility when compared 

 with the Guano, a substance the excremental nature of which 

 has been indubitably established by the chemical analysis of 

 Klaproth *, Fourcroy, and Vauquelin -f*. This substance, ne- 

 vertheless, forms on the coasts of Peru deposits of such extent, 

 that, at first sight, we have some difficulty in admitting it to be 

 the dung of sea birds, which once rested here at night, although 

 upon considering all its relations, this can alone be its true na- 

 ture. 



• Beitrage, part iv. p. 199. gives the following as its composition : In 100 

 parts, 16 ammoniacal uric acid, 10 phosphate of lime, 12*75 oxalate of lime, 4 

 silica, 0*5 common salt, 28 arenaceous impurities, and 28*7-5 water and com- 

 bustible animal remains. The French chemists found even 25 per cent, of 

 uric acid. 



t Gehlen*s Journal, vol. vi. p. 679. 



