[ 189 J 
XXXI. Inquiry concerning Magnesian Limestones in 
Somersetshire, Shropshire, and Nottinghamshire, 
To Mr. Tilloch. 
Srr,—Osservine that Inquiries are often made and 
answered in your instructive pages, as to the localities of 
British Minerals, I beg to extract a passage from Sir 
H. Davy’s ‘* Elements of Agricultural Chemistry,’ viz. 
* Magnesian limestones (which, as he has just before said, 
effervesce slowly in diluted nitric acid, or aqua fortis, and 
in so doing render the acid m/ky), are usually coloured 
brown or pale yellow. They are found in Somersetshire, 
Leicesterhire, Derbyshire, Shropshire, Durham, and York- 
shire. ._ I have never met with any in other counties in Eng- 
land: but they abound in many parts of Ireland, particu- 
Jarly near Belfast.” 
I should take it a great favour to be informed by any of 
your Correspondents, of the names and situations of as 
many Quarries or Rocks, having the above characters, in 
either Somerseishire or in Shropshire ? as they are able, 
and whether Sir Humphry is correct in implying that 
Magnesian Limestones are confined to the abovementioned 
six English counties ?—As to Nottinghamshire, either Sir 
Humphry must be wrong, or Mr. Farey, in his Derbyshire 
Report, vol. 1. p. 156, and in his Map, p.97. It may be 
proper to mention, that Mr. Lowe in his Nottingham Re- 
port, p. 104, quotes the authority of Mr. Sikes, an agricud- 
tural chemist, for the Limestones in question containing 
more siliceous earth than those from near Newark or the 
Peak of Derbyshire, and which is supposed to occasion 
those Nottingham Limes to be ‘* weak,” “ hungry,” &c. 
and very inferior for agricultural purposes to more pure 
Limestones. I am 
Your obedient servant, 
September 1, 1813. AN Inquirer. 
P.S. Happening since the above was written to tura to 
your fifth volume, p. 213, &c. I find that Mr. Tennant 
expressly mentions and gives the analysis of Magnesian 
Limestone near Worksop in Nottinghamshire, aud also in 
Northumberland at page 214; query, at what places, if 
auy, besides the continuation of the Durham Rock across 
the mouth of the Tyne? 
XXXII. On 
