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masses of rock. Not the less had the toad-stone a history of its own, 
bearing witness to the intensity of the internal forces of the earth. It 
was the lava of an ancient volcano. Comparing it with a bit of modern 
lava, a porous mass, blown up into this form by the escaping steam and 
gases, it would be seen that in the toad-stone the holes were filled with 
a carbonate of lime. The molten mass was evidently poured out from 
the volcano on to dry land ; thus it became a porous lava, for steam 
and gases could easily escape from it. Again the surface of the earth 
sunk, the waters of the limy oceans covered it, and deposited in its 
interstices the white masses which gave it its singular spotted appear- 
ance, Such was the history of a piece of toad-stone. 
The presence of the metals and their ores in veins through the rocks 
was still one of the most interesting and the profoundest subjects of 
geology. In how far heat, magnetism, electricity, &c., were concerned 
in producing ores, or in giving a direction to them, was still proble- 
matical. But what particularly struck him with regard to the metalli- 
ferous veins of Derbyshire was that they were all perpendicular to the 
horizon and obviously deposited in chinks of the rocks from a liquid 
solution containing them. They, as much as the carbonate of lime, 
were the results of infiltration. Take amass of sulphate of barytes, 
which thus filled up a crack, and in the centre of the barytes were the 
glittering crystals of sulphide of lead. The rocks. and metals of 
Derbyshire, which built up its limestone hills, were beautiful indeed, 
but not the less were they a subject of wonder, when they linked those 
solid masses in their ideas with the singular delicacy of the stems of 
the Encrinites which formed them, waving their feathery arms in 
countless myriads on the floor of the primeval ocean, and building with 
their remains the most romantic, the most lovely, ofall our English hills. 
Between this Mountain Limestone and the coal-bearing strata, lay a 
vast series of sandstone rocks, in some places 1,000 feet thick. This 
yellowish sandstone capped the hills in the neighbourhood of Matlock, 
and stretched away in enormous masses towards the hilly district of 
the Peak. These limestone and sandstone hills were inferior 
to the Carboniferous strata, but all up through them Nature was, as it 
"were, trying her ’prentice hand at producing the wealth of vegetation 
which followed. That limestone had in it masses of our black diamonds, 
strangely mixed with the glittering crystals of calcite. 
The ripple marks on millstone grit told a tale of a shallow sea 
bed alternately dried by the sun and washed by muddy waters. The 
