Ab. ///. 



AN ACCOUNT 



OF THE WHITTEN PLASTER. 



Sharon, 1th Jan. 1800. 

 SIR, 



HEREWITH submit to the examination of the 

 Academy a sample of stone, called by our farmers 

 Whitten Plaster^ from the name of the discoverer, one 

 Thomas Whitten, of Kent, Searching for iron ore up- 

 on his own farm, he, about two years since, came across 

 an inexhaustible quai'ry of this stone. It is found to be 

 an excellent manure ; and though manifestly not a gyp- 

 seous earth, yet it is not inferior to the Plaster of Paris in 

 its effects upon indian corn, and in certain soils, upon 

 clover. It is less friable than the Plaster, but the propri- 

 etor has erected a mill of curious construction, near the 

 quarry, in which it is easily pulverized ; and such is the 

 increasing demand for it, that he anticipates much prof- 

 it from the discovery. Possessing no chemical appara- 

 tus, it has not been in my power to make by any means, 

 a complete analysis of this stone. From the slight at- 

 tempts I have made to decompose it, I am satisfied it is 

 composed of the sulphuric acid in no small proportion, 

 plumbago, and siliceous earth. ^Plumbago, in a simple 

 state, is frequently found in the interstices of the quarry. 

 If I have rightly conjectured its composition, this stone 

 possesses nothing in common with gypsum, excepting 



* A small quantity of this is also forwarded. 



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