Thus it will be seen that while England and Scotland are, in comparison with their extent of surface, bountifully supplied with coal-areas, in the sister island of Ireland coal-producing areas are almost absent.  The isolated beds in Cork and Tipperary, in Tyrone and Antrim, are but the remnants left of what were formerly beds of coal extending the whole breadth and length of Ireland.  Such beds as there remain undoubtedly belong to the base of the coal-measures, and observations all go to show that the surface suffered such extreme denudation subsequent to the growth of the coal-forests, that the wealth which once lay there, has been swept away from the surface which formerly boasted of it.

On the continent of Europe the coal-fields, though not occupying so large a proportion of the surface of the country as in England, are very far from being slight or to be disregarded.  The extent of forest-lands still remaining in Germany and Austria are sufficing for the immediate needs of the districts where some of the best seams occur.  It is only where there is a dearth of handy fuel, ready to be had, perhaps, by the simple felling of a few trees, that man commences to dig into the earth for his fuel.  But although on the continent not yet occupying so prominent a position in public estimation as do coal-fields in Great Britain, those of the former have one conspicuous characteristic, viz., the great thickness of some of the individual seams.

In the coal-field of Midlothian the seams of coal vary from 2 feet to 5 feet in thickness.  One of them is known as the “great seam,” and in spite of its name attains a thickness only of from 8 to 10 feet thick.  There are altogether about thirty seams of coal.  When, however, we pass to the continent, we find many instances, such as that of the coal-field of Central France, in which the seams attain vast thicknesses, many of them actually reaching 40 and 60 feet, and sometimes even 80 feet.  One of the seams in the district of St. Etienne varies from 30 to 70 feet thick, whilst the fifteen to eighteen workable seams give a thickness of 112 feet, although the total area of the field is not great.  Again, in the remarkable basin of the Saone-et-Loire, although there are but ten beds of coal, two of them run from 30 to 60 feet each, whilst at Creusot the main seam actually runs locally to a thickness varying between 40 and 130 feet.

The Belgian coal-field stretches in the form of a narrow strip from 7 to 9 miles wide by about 100 miles long, and is divided into three principal basins.  In that stretching from Liege to Verviers there are eighty-three seams of coal, none of which are less than 3 feet thick.  In the basin of the Sambre, stretching from Namur to Charleroi, there are seventy-three seams which are workable, whilst in that between Mons and Thulin there are no less than one hundred and fifty-seven seams.  The measures here are so folded in zigzag fashion, that in boring in the neighbourhood of Mons to a depth of 350 yards vertical, a single seam was passed through no less than six times.