in the Neighbourhood of Edinburgh. 255 
But, when alternations of coal are included in our considera- 
tion, still more complicated views arise. 
Coal has arisen from the decay of vegetables which grew 
on the spot ; generally in marshy sites, or in shallow waters. If, 
then, we find seams of coal alternating with sandstones, shales, or 
limestones of a fresh-water origin, no inference remains, but that 
oscillatory movements of the earthy crust must have taken place, 
by which land became submerged beneath the surface of a fresh- 
water lake, from which, by a subsequent elevation of the land, it 
has emerged, so as to give rise to a new Flora. And, in the case 
of coal-seams alternating with limestones of marine origin, which 
is also incidental to the coal-field of Mid-Lothian, a similar in- 
ference arises, that dry or marshy land had become submerged be- 
neath marine waters, and had again arisen from the bosom of the 
deep, to be decked with a new flora, and with fresh verdure. 
While all these inferences are suggested by the system of 
strata which I have described, there are still other important cir- 
cumstances to be taken into consideration. 
These alternations of elevation and depression have, in the 
coal-fields of Scotland, been conducted with a freedom from dis- 
turbance which is most remarkable. In few instances, except 
where local eruptions of trap-rock have prevailed, have I found 
derangements of strata marking the junction of ‘marine and flu- 
viatile deposits, or any intervening conglomerate strata, from 
which diluvial effects might: be inferred. Near Bathgate, a lime- 
stone of marine origin may, at. its junction with a fluviatile bed, 
be found to actually graduate into a fresh-water deposit. While 
the great mass of the rock encloses encrinites, corallines, &c., the 
unio appears in its uppermost bed,near its junction with an over- 
lying bed of sandstone, filled with the remains of plants. | East 
of Dunbar, also, no marks of violence whatever. characterise the 
junction of two rocks, where, in the compass of a few inches only, 
we find the encrinites of a bed of limestone, abruptly, though 
quietly, overtopped by a sandstone containing calamites. 
