236 Dr. Cooper on Volcanoes 
~ We must explain, (if we do attempt explanation) a doubt- 
ful fact, by its analogies, not to what we may suppose, but 
“to what we know, and to that only. 
I take a piece of hard clink stone hackly basalt: T offer 
it to the reader, I say to him, “you are a chemist: this 
piece of floetz trap weighs sixteen ounces avoirdupois : how 
much water will it take to dissolve it °” 
Well : but you urge, the argument does not require solu- 
tion, only suspension—be it so. How came these pores, 
in a stone gradually consolidated and indurated from a paste 
coarse or fine, suspended in water? Did you in any other 
case ever witness a similar formation of a stone from’ its 
parts diffused in water? Is not such a product common in 
pseudo-volcanoes and in the slag of furnaces ? 
Again: how can a soft pasty mass, form a rough ragged 
peak as the summit of a mountain ? 
Again: how can a pasty mass find its way upward, for- 
cing asunder, forcing one end upward, and another down- 
ward ofa series of strata of unfathomable depth, till it ar- 
rives at the surface as in the case of Whin-Dykes? Read 
account of Dykes in 4 Geol. trans. and account for them if 
you can by aqueous solution, or aqueous suspension. 
Look at the ice in winter in any of our great rivers, espe- 
cially at the time of their breaking up in the spring. ‘The 
exact analogy of peaks, rough summits, prominencies of all 
shapes and sizes, and in all directions, rough masses formed 
one over another, the result of great presure a tergo of li- 
uid masses suddenly congealed, will strike you at once. 
* The fields of extinct Volcanoes which I have had the 
opportunity of examining (says M’Clure, 1 trans. of ‘the 
Philad. Academy of Sciences, p. 332) were as similar as 
possible in their component parts and relative position. An 
extensive field round Orlot—near Hamila, and at Cap du 
Gat in Spain—round Rome—between Rome and Florence, 
and in the Vincentin in Italy—in Auvergne in F'rance— 
round Andernack on the Rhine—at Cassel in Germany— 
all of them, leave no doubt on my mind of their voleanie or- 
igin. In all of them I found abundance of Basalt; in some 
of them the greatest part of the solid Lavas was in the 
form of basalt. The Austrian police prevented me twice 
from examining Hungary, but I have seen repeated collec- 
