FOSSILIFEROUS HEMATITE NODULES IN LEICESTERSHIRE. 37 
that there went on, simultaneously with these accumulations 
in organic matter from without, a more or less regular inflow 
or deposition of iron, &c., derived possibly from a volcanic 
source (hot springs), or by percolation out of rocks containing 
much iron, situated at a higher level. But in whatever way 
the mineral did get into the place, it would, I imagine, be in a 
state of solution, and was gradually precipitated or deposited 
upon the bottoms and sides of the rocky openings in such a 
manner as to produce the various structures noticed in the 
fragments and organised nodules. The magnetic properties 
were possibly introduced during the progress of this formation, 
probably by electric currents set up along certain lines or 
cracks having some relation to a magnetic meridian. To 
account for the gritty and porphyritic varieties of the haematite 
we must presume that the enclosing rocks were partly com¬ 
posed of quartz—vein-quartz was probably there. Now the 
oxide of iron would naturally act upon the quartz, and to a 
greater or less degree actually replace it. In this kind of way 
we may, I think, reasonably conclude that the group of forms 
which seem to pass by insensible gradations from the ore of 
almost chemical purity to the very earthy kinds has been 
brought about. This state of things went on until the deposit 
of hsematitic matter either tilled the cavities in the rocks or a 
change of conditions came on which terminated it. The rest 
of the story is soon told. After a lapse of time (thousands of 
years perhaps), the tremendous earth-movements which bent 
and in other ways disturbed the coal measures and their 
surroundings, caused the breaking up of the deposit of 
haematite, and the waves obtaining access to its remains 
tumbled and rolled them about for long ages ; large masses 
of ice bore down upon them, crushing and breaking them still 
smaller, even to powder; and, lastly, having been thus shaped 
as we now find them, they became buried in a kind of clay or 
muddy mixture along with fragments of other rocks of probably 
more than one geological period, of older date than the coal 
measures. 
The above theory is, of course, purely hypothetical. It is 
based solely upon negative evidence, and as such our readers 
will be able to draw their own conclusions. The chief 
objection to it I take to be—the external forms of many of 
the specimens, their even outline, and the character of the 
hollows, wrinkles, and cracks both upon the surface and in 
the interior of many. The source of the chief ingredient— 
iron—too, is extremely difficult to account for. 
(To be continued.) 
