« EelmineJätka »
Art. 1.- The Silurian System, founded on Geological Researches
in the Counties of Salop, Hereford, fc.; with Descriptions of the Coal-Fields and Overlying Formations. By RODERICK IMPEY MURCHISON, F.R.S. With a Map, Sections, and numerous Plates. 4to. London: 1839.
some observations on the supposed equivalents of the English. Silurian' strata in other parts of Europe ; but as the comparative enquiries connected with this subject are not yet fully published, and perhaps are still attended with some obscurity, we have resolved to confine ourselves at present to the result of Mr Murchison's examination of a series of ancient rocks, which he has here described with such ability and success as to place him in the first rank of practical geologists. The great price, as well as the intrinsic value of his book, induces us to give an account of its contents without further delay.
The subjoined geological sketch of England, which is reduced from one of the author's illustrations, will enable our readers, with the assistance of any common map on a larger scale, to form some notion of the situation and extent of what is now to be called in geology the Silurian Region,'-a name taken from a tract upon the confines of England and Wales, but principally in the latter territory, * the inhabitants of which are distinguished in history for their persevering opposition to the Romans, under
* A farm near the centre of this district, not far from the town of New Radnor, bears the name of Siluria in the Ordnance Map.
VOL. LXXIII. NO. CXLVII.
Caradoc, whose name and exploits are still associated with many scenes and local traditions in Shropshire and Wales.
It may seem perhaps extraordinary, that while geology has been cultivated with remarkable energy in this country, a district so extensive, and of such great interest as this tract will be found to possess, should have remained almost absolutely unknown till within the last ten years. But a consideration of what we shall lay before our readers, will in some measure explain this anomaly; while it will show the enterprize and sagacity that first led Mr Murchison to the task which he has so skilfully worked out: and this retrospect is the more necessary, as his introductory chapter is much less satisfactory than might have been expected-giving only a loose and general statement