94 FOSSILIFEROUS HAEMATITE NODULES IN LEICESTERSHIRE. 
which he subsequently found to possess poles, sufficiently 
strongly magnetic to cause the specimen to point north and 
south when freely suspended and clear of attraction by iron. 
In attempting to account for the extreme hardness and 
compactness of the ore, it would appear that the original 
carbonates were capable of combining with or taking up a 
very large quantity of ferric oxide without any increase in size, 
that this chemical change was accompanied by a re-arrange¬ 
ment of the particles, and I may suggest that possibly electricity 
had something to do with it, though I am very sceptical on this 
point. It seems difficult to resist the conclusion, that in the 
case of the haematite nodules of nearly chemical purity, the 
carbonates from which they have been derived must have 
been themselves of great purity. The coarser stones,-—those 
presenting a gritty, flinty, and porphyritic appearance—I 
look upon as probably the only remaining fragments, other 
than the hagmatite, of the denuded coal measures contributing 
to form the breccias. The rest of the strata—the coals, 
clays, shales, and softer beds,—only exist in the Permians 
in the shape of coarse gravelly sediment, mud, and perhaps a 
few broken lumps which may have escaped destruction. 
It may be said by some that if the pseudomorphic process 
in clay-ironstones can be proved to have taken place in situ in 
the coal-measures, as in the above-mentioned instance, why 
may not these haematite nodules have been formed in those 
rocks long before they became turned out and re-deposited in 
the Permians ? My answer is that we know of no rocks 
from which the iron could produce the pseudomorphic action 
in the underlying coal measures ever having been formed in 
the upper coal series, or before the Permian period set in. I 
believe our British coal-beds, where found of a red colour 
(known as “ red rocks ”), are held to have become this colour 
by iron-staining from newer rocks.* This reddening or 
blotching is due no doubt to the oxidation of the iron in the 
rocks, and the colouring is naturally most intense in rocks 
like clay-ironstone, which contain a large amount of iron. 
It is evident that the above-described features and 
properties possessed by the haematite nodules are facts which 
harmonise singularly well with the theory of pseudomor¬ 
phism, while they are much less reconcilable with that of 
sublimation or the cave or fissure-formed deposits. This 
conclusion, namely, that the ore is of Permian age, is 
supported by the fact that many of the largest and richest 
* The instance of the Froghall hreinatite deposits in the lower 
coal-series is of course an exception. 
