14 On Plaister of Paris. 
countries, and used as a top dressing. But the quantity 
ary is enormous, compared with that of the 
au here is no country where limestone lands are to 
be Gust. in greater proportion, than in this. I know 
many farmers of limestone lands, who use _plaister. 
The results of their practice, much the same with those ~ 
on other soils. It depends on the texture and staple, of 
the upper stratum of soil. Limestone is here found 
under clay, loam, and sand. In our coal countries, ge- 
nerally under c/ay. It is curious to observe the gene- 
ral uniformity of the strata, in our western country, 
beyond the mountains; where in many parts, they 
scarcely ever sink a well, without finding clay, coal, lime- 
stone, and freestone, or slate, in strata, each of from four 
to six feet thick. The clay is generally on the surface, 
but it frequently happens otherwise. 
6. By a recurrence to the facts in the foregoing 
collection, it will appear, that the idea of plaister not 
being beneficial, where /ands have been long under cul- 
tivation, is unfounded. Mr. Robert’s lands have been 
cleared 90 or 100 years. Some of mine above 60, Mr. 
Sellers’s is an old farm, and so are those of Mr. Duf- 
field and Mr. Price. 
OO 
T have lately been informed, in a letter from Robert 
Barclay Esq. of London, a worthy member of our soci- 
ety, that plaister succeeds in some parts of England ; 
where it has been used with various success; and 
often, in that kingdom, without any benefit. Mr. Bar- 
clay writes, under date of 31st July, 1810.—— 
