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less protected, whilst the higher ridges, as has been previously 
indicated, suffered most. The limestone ridges now existing 
in the Northern portion of the South Wales coal field rise some 
1,200ft. above sea level, but on its Southern outcroppings it is 
only about 500ft. The highest point in Dean Forest is also 
about 1,000ft. above sea level. 
Geological evidence proves that the coal deposits existed 
in a more general form than is commonly supposed. It must, 
in fact, have extended over a considerable portion of England, 
Scotland, and Ireland before the intervening space between 
the two islands, and also that to the South-West of Land’s 
End, became depressed as table-land a little below the sea 
level. Without doubt the French and Belgian coal-field, at 
least, were at one time joined to those of Great Bitain, the 
connecting link having been severed by various natural causes. 
There is ample evidence to prove that in the time of the 
Ancient Britons the whole of the island now called England 
was covered by dense forests. If therefore that is an admitted 
fact referring to a thing which existed not further back than 
2,000 years, how much more dense and general must have been 
those forests which existed during the latter part of the 
Devonian, Carboniferous, and more recent periods, when the 
surface of the earth and atmosphere offered better conditions 
for the growth of vegetation. It is difficult to accept the 
theory of some Geologists, which assumes that the isolated — 
existence of some of the coal fields is due more to mere patches 
of forests—which they think were not continuous and general 
—than to any other cause. 
The recent borings carried on at Dover to prove the nature 
of the rocks in connection with the formation of the proposed 
Channel Tunnel are said to have been carried into the coal 
measures, but of what age has not been stated. However, it 
has been reported that workable seams of coal were discovered, 
but this requires proof. It can easily be conceived that the 
discovery of such a coal field would prove to be of the greatest 
importance, not only in a commercial sense, but also as a 
scientific victory, which all true Geologists would hail with the 
greatest enthusiasm. 
