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by the fact that if not so serious, earthquakes are, at any rate, 
most frequent in such localities. At the destruction of Riomba 
there was no eruption of the volcano close by ; the usual openings, 
doubtless, having been closed up, there was no relief for the 
internal pressure. 
The supposition that the shocks of earthquakes are in any way 
caused by the bursting powers of confined vapours is no new one. 
In fact, I find in an interesting work on the subject, written 
more than a hundred years, by Dr. Stukeley, which has beer 
kindly placed in my hands by a member of our society, an allusion 
to those who hold what he considers this mistaken idea ; his view 
of the matter being that the origin of these phenomena is entirely 
to be traced to electricity. But, clear as his arguments are, they 
do not appear to me convincing, and are certainly not endorsed 
by the best authorities since his time. His theory appears to 
have been that the origin of earthquakes was to be found in 
electric action commencing above ground, and not in the earth 
below us; and in support of this he alludes to the invariably 
sultry weather preceding them. I believe this to be a mistake, 
and though I have certainly felt what the Cornhill writer calls 
‘earthquake weather ” before a shock, yet I have known very 
many instances where there was no such indication at all. 
Although the idea of the centre of our globe being a molten 
mass may be no longer entertained, yet all must admit that there 
exists great internal heat, varying in depth and intensity, but at 
no great distance below our feet. Science, which has told us so 
much about the heavenly bodies millions of miles away, has been 
able, for obvious reasons, to penetrate comparatively but a short 
way through the crust of our own planet : yet the eruptions in so 
many parts of the world, varying from the devastating effects of 
the great voleanoes to the bubbling Sulis water within a few yards 
of us, tell us plainly of subterranean heat: how produced who 
can say? But may we not imagine this heat intensified at times 
by the passage of electro-magnetic currents, or possibly by some 
