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have seen, pebbles of sand-rock which must have come from 
older strata than that conglomerate itself. But we have no 
sign as to the nature of that rock on which the older strata 
were laid down. In popular geology, with its vertical up- 
heavals, we have no provision for anything below, that could 
sustain the now raised sea-bed on which these pebbles were 
strewed. Heat is only a state of matter analogous to motion, 
and to have the heat we must have something to be heated ; 
but as at present taught, we lack this actual substrate which 
is so indispensable. The truth is, we are worse off than 
Archimedes when he would have moved the world : we 
have neither fulcrum nor lever ! Then we are taught to 
believe in masses equally great, that sink down without 
our getting any idea of unoccupied space below. Even 
molten matter requires space, but the molten character of the 
inner centre is now seen to be a “ myth and how to account 
for the subsidence of vast continents is as difficult, if not more 
difficult, than to account for their upheaval. There is one 
among some other curious exceptions to this vertical rule 
which we have noticed in Sir Charles Ly ell's explanation of 
the position of a mass of gneiss 1,000 feet thick and 15,000 
feet long, which he found in the Alps “ not only resting 
upon, but also again covered by strata containing oolitic 
fossilsA* He supposes “ great solid wedges of intrusive 
gneiss to have been forced in laterally between strata,” to 
which he found them to be in many sections unconformable. 
This is a great step out of the usual road of movement. It is 
amusing to see how happy many great minds are in their 
enjoyment of vertical motion alone. Their sea-beds sink 
to nowhere, and their mountains and continents rise from 
nowhere; but they themselves are not troubled with the 
incongruity in the dream ! Is it not possible that there may 
be a horizontal motion of the earth's surface ? May not 
the travelling of Icelandic snows bear some analogy to the 
changing position of the masses of the earth's surface ? It is 
surely more philosophical to speculate with the greatest of all 
natural forces and the only possible direction of motion in 
view, than to leave them out of sight, imagining vast effects 
without adequate causes, risings without lever or fulcrum, 
sinkings without empty space below, and when difficulty is 
hinted, merely to pray for time ! But like all else that is 
really fundamental in popular geology, this vertical upheaval 
* Lyell’s Elements of Geology, edition 1866, p. 752. This whole passage 
in one of Sir Charles's latest editions is strikingly indicative of confusion of 
idea as to the nature and position of the strata on which he is remarking- ; 
however unpardonable it may be in us to think so. 
