It is an old remark, that much of the prosperity attending the manufacture of iron in Great Britain has resulted from the circumstance that the ore, the fuel, and the flux are mostly associated minerals in the same locality; and, although this is typically true as regards the mineral basin which forms the subject of the present article, it is some-what curious that, in all probability, the discovery of the fuel in this instance dates much posteriorly to the employment of the ore, so that iron-making, had become an active branch of industry in this district long prior to any of the numerous seams of coal being worked; and, what is equally likely, before even their existence was known. If we look into any of the early histories of Gloucestershire, we find that, while abundant mention is made of the iron-mines and the smelting furnaces, no notice whatever is afforded of the coal, fully warranting the supposition that the discovery of the deposits had not then been made. I t will, perhaps, form an interesting preface to this paper, if, in connection with this latter circumstance, before entering upon the geological and lithological features of the ironstone formations, which are special and of the greatest interest, I give a sketch of the commercial history of the locality, past and present.

In tracing the progress made in the metallurgy of iron in this country, the Forest of Dean claims to have been among the first localities where the manufacture of that metal was established.