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Are all the beds marked on the Geological Survey Map as 
Kimeridge Clay, at Longleat Park, Witham Park, &c., really 
Kimeridge Clay? Fossil evidence would no doubt decide these 
points, which are not very certain according to some notes 
furnished to me by Mr. W. T. Aveline; the Gault may be in 
part at any rate represented at these localities. 
Among other interesting questions to which answers are yet 
wanted are the following :—(1) Whether the fan-shaped structure 
exhibited in the Mountain Limestone on the high road west of 
Dolberry Camp, be an actual inversion, or merely a sharp 
synclinal ; (2) What is the relation that the several patches of 
Mountain Limestone represented on the Geological Survey Map 
(sheet 35) as occurring in the midst of the Coal-measures of 
Clapton-in-Gordano, bear to the rocks surrounding them ; and 
whether the explanation of their position may help to explain the 
apparently similar masses of Mountain Limestone at Vobster and 
Luckington ; (3) To what cause does the Harptree Chert owe its 
origin, was it due to the action of heated water during some 
igneous eruption, or was the metamorphism (for such it certainly 
is) produced by the former presence of some hot-springs like those 
at Bath? (4) What is the exact relation of the Igneous rocks, 
discovered near Stoke Lane by Mr. Moore, to the Old Red 
Sandstone? (5) Are there any certain evidences of the Glacial 
Period in Somersetshire ; any travelled boulders ? 
Researches upon Lithology, principally those carried or within 
the last ten years, show how important an aid is the microscope 
in the true identification of the Eruptive rocks. It is now-a-days 
rash to identify in any but a general way such rocks in the field ; 
to give to them names consistent with their true mineral compo- 
sition can only be done with accuracy from an examination of 
thin slices from the rocks under the microscope. Here is a wide 
field of study! Somersetshire, it is true, compared with many other 
English counties, can boast of but few exposures of Igneous rock. 
Those in the Mendip country are pretty well known, and my 
