114 Lord Greenock on the Coal Formation of the 
The Campsie Hills particularly, in the neighbourhood of Kil- 
syth, exhibit several magnificent sections illustrative of the pe- 
riod and manner of their elevation, when viewed in the relations 
they are there seen to bear to the carboniferous series. In the 
Bathgate Hills, and in Stirlingshire, coal and limestone are 
worked beneath columnar trap; and, indeed, the whole country 
occupied by the Scottish coal-measures displays more or less the 
effects produced by the influence of such igneous hills, or of the 
dykes connected with them, some of the former rising into moun- 
tain masses, others forming detached hills, either lofty and 
rugged, or scarcely elevated above the level of the surrounding 
country ; while many of the latter do not penetrate to the sur- 
face, but remain at greater or less depths beneath it, producing 
much disturbance in the strata below, as well as many of the dis- 
locations and elevations that are observed above ground, although 
the cause itself may not be perceptible. 
When viewed collectively, a certain degree of parallelism may 
be observed in the principal chains formed by the hills of this 
nature, their general bearing being from the westward of south 
to the eastward of north, which corresponds with the general 
strike of the fossiliferous rocks ; and they sometimes appear to 
assume a circular arrangement, encompassing valleys or basins of 
greater or less extent. This, however, cannot be said to be the 
case with respect to the smaller groups or insulated masses, many 
of which seem to have been protruded through the strata at dif- 
ferent times, and under varying circumstances, without any ap- 
parent order or regularity ; and the dykes are found to proceed 
in every direction from the principal masses, in some cases ap- 
pearing to radiate from them as centres. 
Besides the interruption occasioned to the coal measures by 
the elevation of the hills, by which the coal-fields are now sepa- 
rated from each other, their connection has in many instances 
been more or less cut off by rivers, estuaries, or portions of the 
sea, the beds of which have been formed in these deposits. This 
