On the Geology of Moffat, Dtimfriessldre. 389 
anything satisfactory could be determined. The examination 
of the district, however, shows that the conclusion of Dr 
Singer, though correct theoretically, is really incorrect ; for it 
is evident at the various junctions of the formations, as in the 
Newton, Hartfell, or Frenchland Burns, that the unconform- 
able sandstone rests immediately on the upturned edges of the 
Silurian strata. 
The occurrence of the black, coal-looking, anthracitic Silu- 
rian shales in many localities, has led to the belief that coal 
existed in their neighbourhood, and has caused several abor- 
tive attempts to reach it to be made, in opposition to the 
published opinions of the Busbys, Jameson, and Singer. It 
is remarkable that landed proprietors in every Silurian region 
have been induced to spend their money in vain attempts at 
searching for coal, where these anthracitic shales occur, on 
the recommendation of empirics, and generally in opposition 
to the published or known testimony of scientific men. 
The Trap Dyke. 
The Trap Dyke has been quarried for some years at a point 
where it projects on the surface near the summit of the Loch- 
house Hill. It supplies the bluish stone which has been 
extensively used in the recent buildings in Moffat. Its rela- 
tion to the strata, through which it is intruded, can be best 
seen in the bed of the Evan, a little above Longbedholm Cot- 
tage. Its direction is N.W. by S.E. Beyond the point where 
it crosses the Evan, it may be traced in a N.W. direction until 
it crosses the line of the Caledonian Railway. In the oppo- 
site direction it has been quarried on Evan road side. It 
pushes out into considerable prominences in several places on 
the Coates Hill. It is also quarried, as has been said, on the 
Lochhouse Hill, and again in a plantation on the farm of 
Woodhead. Mr David Stewart has observed quarries in it 
in Dryfesdale and Eskdale. I believe it to be the same dyke 
that occurs again at Langholm. 
It is a compact, fine-grained greenstone, distinctly crystal- 
line in the centre, and becoming compact and amorphous at 
the edges. It is 32 feet wide at the quarry on the Evan 
road. 
