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colliery shafts sinking through it. The probability of this being 
the case in connection with our hot springs is still further 
enhanced by the fact that it is situated at the lowest point of 
outlet of a wide expanse of pebble beach deposit, extending over 
nearly the whole of the Somerset coal basin. And, also, our hot 
springs having been flowing even before the existence of the 
beach itself, there can be no doubt whatever that the natural 
outlet for the hot water, provided also a natural outlet for the 
cold water from the Conglomerate mingled with it ; thereby 
reducing its temperature by probably 50 per cent. This 
_important consideration gives immense force to a statement made 
by Sir Charles Lyell in his address, at the opening of the meeting 
of the British Association at Bath in 1864. 
Wewill now consider, what extent our thermal springs may suffer 
by the sudden chill occasioned by the influx of cold water from the 
Conglomerate and the Lias formation through which it passes in 
its upward course. The heat of the water certainly ought to be 
very much greater than it is according to all the computations we 
are enabled to make. When Sir Chas. Lyell delivered his address, 
the voleanic origin of the formation of Coal basins and other 
disturbances had not received the attention it deserved ; little 
notice was paid to the water trickling into a course which 
conveyed it down thousands of yards through rocks which had 
undergone great chemical and structural change through prox- 
_ imity with volcanic heat. Sir Chas. Lyell in the same address 
gave us a good idea of what volcanic heat is, he says: ‘‘ We 
learn from Bunsen’s experiments on the Great Geyser in 
Iceland, that at the depth of only 74 feet at the bottom of a 
tube, a column of water may be in a state of rest, and yet possess 
a heat of 120° Centigrade or 248° F. What then may not be the 
temperature of such water at the depth of a few thousand feet ? 
It might soon attain a white heat under pressure, and as to lava 
they that have beheld its issue as I did in 1858 from the south 
_ western flank of Vesuvius, with a surface white and glowing like 
