Mr. Henwood on the Stcatn-Engines of Cornwall. ' 323 



found fragments of pearly shell in other specimens of copro- 

 lite from the same place. A small fragment of quartz occurring 

 within a coprolite may have existed in the stomach of some 

 animal that was devoured by the saurian or fish, from which 

 such coprolite has been derived ; or it may have been acci- 

 dentally swallowed by the animals in gorging their prey at the 

 bottom of the sea. 



The shape and size of the American coprolite accords suf- 

 ficiently with those we find in the inferior chalk of Sussex, to 

 add probability to Mr. Dekay's opinion, that it is from the 

 inferior chalk or green-sand formation in New Jersey. And 

 whatever may be its geological position, the discovery of this 

 specimen in North America encourages me to anticipate the 

 speedy verification of my conjecture, that coprolites will be 

 found to occur universally wherever there are fossil I'emains 

 of saurians, or of any other carnivorous animals that swal- 

 lowed their prey entire, or which, like dogs and hyaenas, de- 

 voured bones as well as flesh. 



1 remain. Dear Sir, yours, &c. 

 To R. Tai/lor, Esq. Wm. Buckland. 



XLVI. Observations on some late Statements hy Mr. Farey re- 

 specting the Sfeam-Engines of Cornwall. By Wm. J. Hen- 

 wood, F.G.S. 



To Richard Taylor, Esq. F.L.S. F.G.S. ^r.^-c. 

 Sir, 

 TN a late Number of the Phil. Mag. and Annals*, you have 

 -*- reprinted a part of Mr. Farey's evidence on the patent laws, 

 in which are statements injurious to some of the improvers and 

 builders of steam-engines. The substance of those to which 

 I object, may be stated as follows : 



Isl, Ascribing to Mr. Woolf the " invention of working 

 steam-engines by high-pressure steam acting expan- 

 sively." 

 2ndly, " The difference between the cost of coal for a given 

 force of engines in 1813 and at present, would ab- 

 sorb tlie profit of all the deep mining that is now car- 

 ried on in Cornwall." 

 Srdly, Stating " that all the engines in the county are on 

 Mr.WooH's plan." 



1st, I believe the invention of expansive working has been 



• FrI). 1H.'{0. N.S. vol. vii.p. \52. 



2 T 2 with 



