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coal measures. The profitable Canobie coalfield, like that 
at Common in Ayrshire, belongs to the middle or valuable 
coalfield; but there is also at Canobie a great thickness of 
upper coal measures containing a seam of limestone, in all 
respects like the Ballochmoyle Braes, near Catrine, the 
Ardwick and Leebotwood limestones. Consequently, the 
permian fault should be called by some other name, say 
the Great South fault. 
Practical mining engineers have frequently classed all 
the red- and variegated beds which they find in the 
upper part of the coal measures as “red measures” or 
permian strata. Now, there is no doubt often great diffi- 
culty in drawing the line of demarcation between the upper 
coal measures and the permian strata, and it is possible 
that, in some sections, one may pass into the other, as 
appears to be the case in the river section above the bridge 
at Canobie, previously alluded to, but in the north-west of 
England this transition is not generally to be seen. The 
further we investigate the organic remains of these two 
formations probably more genera and species will be found 
to be common to both than is at present supposed ; but in 
all cases where the remains of stigmaria and sjnrorbis carbo- 
narius ( microconchus ) have been found in the strata the 
Author has termed them carboniferous. In the absence of 
organic remains, which is generally the rule and not the 
exception, the permian character of the strata has been 
decided by the mechanical character of the deposits and the 
order of superposition, the beds of breccia and the soft red 
sandstone generally affording pretty good evidence of the 
permian age of the strata over a great extent of country, and 
varying with the character of the older rocks found in situ in 
the district. If the permian beds are taken as the Moat sand- 
stone, the red shales with gypsum and four breccias lying in soft 
red sandstone at Canobie and Biddings, their identification 
is pretty easy; but in continuing them downwards into the 
