MODERN CONGLOMERATES. 
137 
and the phenomena of their deposit; I view the 
matter in connexion with a supernatural cause 
acting on the earth and infused into tho materials 
employed.* 
Amongst alluvial deposits is reckoned peat, a 
substance composed of decayed plants peculiar to 
damp soils. Of this alluvium we have an abundance 
on Dartmoor and its vicinity ; where it has attained 
to some considerable thickness it is cut into turf, 
which when dried is used in the parishes of, and 
* In Mantell’s “ Wonders of Geology” a plate is given of some 
ancient coins imbedded in iron-stone, shewing of course the action 
of causes now existing, equal in that instance to what has also 
occurred in very ancient periods. A case of the same kind though 
far less decisive has come under my notice, and may be here 
introduced as illustrative of the geological changes actually pro¬ 
ceeding in our own day. A mass of stone of curious shape was 
picked up on one of our beaches, and it being uncertain in character 
was afterwards broken in order to view the interior. Its centre 
was a horse-shoe greatly eroded, around which had gradually 
congregated the sand of the shore to a considerable thickness, and 
with so great solidity and compactness as to wear the appearance 
of the commoner and less dense sandstones of the Devon coast. 
This fact therefore even alone will justify a belief in the limited 
geological operations now proceeding, though they are for the 
most part different even in quality and character, not to say 
amount, from those which were conducted under especial auspices 
in ages past. 
If the reader will refer to p. 58 of the above work, he will find 
what I was unaware of till after I had written the preceding para¬ 
graph, namely, that a precisely analogous specimen was in possession 
of the author, and that he attributes the consolidation to the 
ferruginous matter distributed through the mass,—it is termed 
indeed “ ferruginous conglomerate.” I may here also add, that in 
the sister county of Cornwall a most remarkable proof is afforded 
of recent operations in nature, by which a rock is at the present 
time in an actual state of formation, and similar in its composition 
S 
