324 The New Ivon-fields of England. [ July, 
man’s inventive powers to find out their uses, and in this way, more 
perhaps than in any other, nature is the instructor of art. 
It is an old remark, that the most useful of all our metals is the 
most abundantly diffused through the rocks and strata of our earth. 
In some parts of the world nearly pure ores of iron occur in masses 
of sufficient magnitude to constitute hills, or parts of mountains. 
This is the case in Scandinavia, parts of Central Europe, and Southern 
India, where magnetite assumes the proportions rather of a rock 
than of an ore.* In our own country, however, we have no such 
examples of the massive accumulation of pure iron-ore, but the 
difficiency is amply compensated for by the frequency of its occurrence 
in combination with other substances. Before entering more fully 
on this subject, I wish to make one or two remarks on a point of 
nomenclature, which it would be of advantage to adopt when speak- 
ing of the different forms in which iron-ores occur. The classifi- 
cation of these ores into two groups, to be called “iron-ores” (proper) 
and ‘‘iron-stones” respectively, will be easily apprehended by all 
persons familiar with the manufacture of iron; and the various 
modes of its occurrence. The distinction holds good for the most 
part, both mineralogically and stratigraphically, and is indeed often 
unconsciously used in commerce. Under the head of “ iron-ores” 
(proper) might be classed those which occur either in the form of 
veins or lodes, and pockets, such as the red hematites of North 
Lancashire, Cumberland, and the Mendip Hills, the brown hama- 
tites of the Forest of Dean, South Wales, and Cornwall, and the 
magnetite of Cornwall, Devonshire, and Sweden. Now all these 
ores are amongst the richest in iron, are but slightly debased by any 
foreign substances, and they occur in the form of the ores of other 
metals, such as copper and lead, or approximately so. The “iron- 
stones,” on the other hand, are of a more earthy character, are 
consequently not so rich, and partake more or less of the laminated 
or bedded structure of the strata with which they are associated. 
Under this head may be classed the black bands and clay-iron- 
stones of the coal-measures, the iron-bearing beds of the Lias, Oolite, 
Greensand, and Wealden formations. There are, doubtless, some 
rare cases in which the ores partake of an intermediate character, 
but in the great majority of cases they may be arranged under one 
or other of these heads. 
The ores which we are about to consider are of the latter 
description. They are essentially zron-stones, and occur, toa greater 
or less degree, in a stratified form, partaking of the aqueous origin 
of their associated rocks. So similar indeed are they to ordinary 
strata, and so little calculated to arrest attention, that for hundreds 
of years they had been quarried for building purposes, or even for- 
* See the description of the Magnetic Ivon-ore of the districts of Trichinopoly, 
Salem, and South Arcot, in this Journal, No. VL, p. 342. 
