290 
Gaiite, so that it may be of greater extent than we are at present 
aware. Its outcrop line on Sanders’ map is generally correct, 
but there are two exceptions to this, which may be noticed in 
passing. In a field on the north-west side of the Newbury 
Railway bridge at Bilboa, there are the remains of a small trial 
shaft, the débris from which consist of Coal shales, whereas at the 
point referred to, and for nearly a hundred yards to the north 
of it, Mr. Sanders has shewn Mountain Limestone. On the 
other hand, near Page house, there are indications that the 
patch may extend farther westward than Mr. Sanders. has 
mapped it. I base this statement on the discovery of a protrud- 
ing block of Limestone, about 40 yards from the grounds of 
Page house. I have been unable to trace its connexion with the 
Upper Vobster area, and there may possibly be no connexion ; 
but it has all the appearance of being in situ, and if so, it extends 
the Limestone some 70 yards farther westward than hitherto 
noted (see dotted lines on diagram), a fact which, as I will pre- 
sently shew, is of considerable importance. 
The third and last of these isolated areas of Limestone occurs 
at Luckington, about 800 yards to the west of that last described, 
and about 1,900 yards from the Limestone of the Mendip range. 
It is less exposed than either of the other areas, but it can be well 
examined in a quarry by the road-side, and its general outline can 
be readily traced. Its extreme length is about 450 yards, and it is 
from 50 to 120 yards in width. The dip is very variable, being 
south at one point and east in another. With regard to all these 
Limestones, it may be remarked, that from their general appearance 
and their comparatively nonfossiliferous character, they probably 
belong to the upper portion of the Carboniferous Limestone 
formation. It is impossible to distinguish between specimens 
obtained from the less disturbed beds in these outliers, and others 
obtained from the Mendips, at Soho, but in the former there is a 
greater prevalence of sparry joints: the fissures, produced by 
disturbance, having probably become filled with that substance. 
