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measures is, that it is found to repose directly upon the 
Carboniferous Limestone, except on the Eastern side, where 
there is an overlap, and in contact with the Old Red Sandstone. 
Mr Maclauchlan’s section shows this, and his map also indicates 
that the limestone is absent for a distance of half a mile. The 
Geological map, however, does not show that it is missing for 
so great a distance. These coal measures are considered to be 
identical with those found in the Millstone Grit series of the 
Central and North-Western portion of Great Britain. 
It has hitherto remained a question whether the Carboni- 
_ferous Limestone, and consequently the coal measures of the 
Forest of Dean, have extended to Newent and the Malvern 
Hills. The patch of coal at Newent is hid for the most part by 
the New Red Sandstone, and is known to repose directly upon 
~ the Old Red; but whether it was deposited there anterior to 
the formation of the Carboniferous Limestone, or subsequently, 
has not been determined with any degree of certainty. The 
late Sir R. I. Murchison was of opinion that there was no 
destruction of the Carboniferous Limestone towards Newent 
before the deposition of the coal measures, but whether he 
believed that the limestone extended so far, or not, nevertheless 
there is strong evidence that it extended much farther. No 
traces of the Millstone Grit existed at Howell’s Hill according 
to Maclauchlan, but it is marked upon the Geological map. 
Personally, however, the author has no evidence, but if ever it 
existed there, it must have been carried away, like we have 
shown is the case in other parts of the Forest. The same cause 
has partially removed and thinned out the Mountain Limestone, 
for the coal measures appear to be deposited partly on the 
limestone and partly on the Old Red, the remaining portion of 
the former coming in from the West like a wedge, and dying 
out towards the East, half way under the coal measures. It is 
evident that Murchison inclined to the opinion that the patch 
of coal at Howell’s Hill belonged to the Millstone Grit series. 
If this theory could be fully established we should be justified 
in inferring that a similar deposit of coal took place over the 
entire Forest after the close of the Carboniferous Limestone 
