CARBONIFEROUS OF CAPE BRETON—GILPIN. 103 
sole benefit. The plants grew and fell, and were buried, the 
water of the swamps allowing but a tardy decomposition, until 
a deep peaty mass accumulated. The sub-soil, a clay or loam, 
was filled with rootlets until perhaps no further mineral nourish- 
ment of silica or of potash, etc., was available. Long years this 
swamp, devoid of living vegetation, lay gradually undergoing 
changes consisting chiefly of elimination of water from the 
vegetable matter, until some oscillation of level, per- 
chance a change in the current of some bygone river 
unnamed and unsung deposited on its partly hardened sur- 
face a layer of silt or mud. This went on until hundreds of feet 
of sandstone, shale, coal, fireclay, etc., are now presented. The 
accumulating mass in the slow course of time became firm. 
Pressure, the internal heat of the earth, chemical laws of change 
all combined to make the peaty mass a layer of carbon with a 
small percentage of ash, and of bituminous forming matter; the 
sand layers were cemented by silica into hard sandstone, the 
mud into bituminous or carbonaceous shale ; and the ancient soil 
well robbed of its alkali; and silica became fireclay. 
Almost without exception every bed of coal the miner explores 
has immediately below it a bed of fireclay often filled with car- 
bonized roots. The coal bears in its structure the evidence of its 
vegetable origin, for under the microscope can be seen in it, fruits, 
flowers, and particles of wood fibre, etc. Above the coal comes 
the roof usually of shale or sandstone, often bearing in it at the 
junction with the coal bed, layers of ferns, pressed and preserved 
as in a herbarium; ora full length tree of that ancient forest 
showing in its flattened stem clearly and distinctly its species, 
ete., and recalling with its darkened color the logs found in our 
peat swamps. 
We have now briefly traced the coal seam to its full growth, 
but had nature gone on adding the coral, the chalk, and all the 
varied and immense layers of subsequent formations this pre- 
cious beritage would have been like an estate in chancery, pleasant 
to think about, but a thing unattainable, for we could not have 
sunk shafts some four or five thousand feet to provide our fuel. 
The process of nature which has laid these stores of fossil fuel 
