Page images
PDF
EPUB

eyes. For this reason, among others, the examination of some distant portions of our eastern hemisphere, and of North America, (where the Silurian groups are already known to exist,) is very much to be desired.

In the mean time, whatever be the destiny of the system, the beautiful volume which we have just examined, will remain as a permanent contribution to our knowledge of the structure of a most interesting portion of our country, and of the globe-a record of intelligence and perseverance, of which its author may be justly proud. We have only to add our earnest hope and expectation, that Professor Sedgwick will soon embody and publish the detail of his valuable labours, on the most ancient groups of England and Wales; with such illustrations of maps, sections, and representations of fossils—the pièces justificatives of geological history—as will give to the student of English geology the satisfaction of knowing, that the whole of our series of rocks has been described, in such a manner as to afford a solid and extended foundation for the comparisons and reasonings of those who are to succeed us.

From the great thickness alone of the Silurian groups, it would have been reasonable to anticipate the discovery of similar masses in other parts, at least of Europe, throughout which, rocks of the transition class are very widely diffused. And from the moment when the existence of these strata was established in England and Wales, it became necessary that the transition rocks,' especially at their junction with the secondary series, should every where be rigorously examined anew. Evidence, indeed, has already been obtained, which makes it probable that formations of this age-containing fossils not merely analogous, but identical even in their species, with those of the Silurian region-exist extensively in Russia, Norway, North America, the Falkland Islands, and South Africa.* And questions of the highest importance, as well as novelty, are thus brought into view, with respect to the former condition and distribution of organized bodies, and to the laws of geological sedimentary deposition.

Had we proposed at present to enter upon this most interesting enquiry, we should have called the attention of our readers to an able statement of many of the views connected with it, in a paper

read before the Geological Society of France during the

* Report, &c., Communications to Sections, vol. iv. p. 59.60.

last year, by M. de Verneuil, * who accompanied Mr Murchison in a recent examination of the ancient rooks of Northern Russia; and we shall so far anticipate the statement, which may soon be expected from these two gentlemen on the result of their expedition, as to say, that equivalents of the carboniferous limestone, the old red sandstone, and the Silurian system, have been ascertained to exist in that region very extensively. †

The recent geological surveys of the United States concur with private information from that country, to prove that Silurian fossils are found there to such an extent, that an exact comparison of the American with the English system is of great importance to the progress of the subject. M. de Verneuil, in the paper above referred to, had shown that the fossils of our carboniferous and Silurian systems occur in the state of Ohio; and, since this article has been in progress, a recent collection of geological Reports' on the state of New York, has come into our hands, which contains new proofs of the existence of the system in that province also. In two former series of these documents, published before the appearance of Mr Murchison's book, Mr T. A. Courad—' Palæontologist to the New York survey'-had mentioned that representatives of the Cambrian and Silurian systemsf appear there; and that it was doubtful whether a more perfect series of transition strata than that of New York,

can be found in any other part of the world.' The latest collection of reports on New York, dated in January 1840, enters more fully into this subject. The vicinity of Schoharie, from which a numerous collection of fossils had been formed by Mr J. Gebhard, affords, according to Mr Courad, one of • the finest geological sections in the whole range of the (Ameri

can) Silurian system, each of the formations being marked by ' a wide terrace, suggesting the idea of a staircase on a large

scale.' In this collection of documents also, Mr James Hall, one of the State Geologists,' speaks with equal decision of the

Silurian groups ;' and mentions the important fact that the old red sandstone, containing Holoptychus nobilissimus, with remains of a Megalichthys, and of a Saurian genus, supposed to be new, forms the limit between the carboniferous and Silurian system,

6

* Bulletin de la Soc. Geol. de France, tom. xi. p. 166–179.

| Report of Geol. Sect. during meeting of British Association at Glasgow, September 1840.

Second Annual Report, 1839 : p. 57, 66. || Reports, &c., 1840: p. 203-4.

§ Sauritolepis Taylori, named in honour of Mr R. C. Taylor, late of London, who first described the sandstone of Glossburg, and suggested its analogy to the old red sandstone of England.-P. 453. Note.

[ocr errors]

and is distinctly above the latter; which fact alone is primâ facie evidence that these groups have been correctly identified. A full list of fossils is given by the reporters; and with every allowance for possible errors—though we cannot enter fully into the comparison without the aid of maps and sections, the resemblance of the region which has afforded these remains to the Silurian tract of England, appears to be sufficiently established. * We shall extract, therefore, a passage from the report of Mr Hall; and we have no doubt that the author of the volume we have just examined, will be gratified by the testimony to the usefulness of his work, thus naturally expressed by a fellow.labourer in a distant country :— Since the publication of Mr Murchison's work, we have been enabled to establish, with great certainty, the analogy

of our rocks with those of the Silurian system, as developed in • England and Wales. In this country, however, the greater * undisturbed range, and apparently better development of par6 ticular members, with more numerous species of organic remains, • enables us to limit our subdivisions within narrower bounds, • and

thus offers greater facility for the study of particular groups.' - The work,' it is added, “ forms an era, and an important one, ' in the development of the older fossiliferous rocks, which have * been so long enveloped in obscurity. It offers inducements to • the study of the same, which have never before been presented :

since, particularly in this part of our country, the rocks of the • Silurian system are better developed than any other, while the • means of studying them with guides have been entirely want. ing. Thus the student, after weary months of labour, aban• dons the subject in despair, being unable to identify the rocks or fossils with any system heretofore published ; and, having made too little progress to systematize the whole, distrusts what • he does know, because it seems inapplicable to what he supposes to be the same rocks, or their equivalents, in another country;'ť

6

* Among the genera mentioned in the reports, which occur also in Mr Murchison's list in the subjoined table, are the following :- - Homolonotus, Asaphus, Calymene, Trinucleus, Agnostus, Bellerophon, Orthoceras, Euomphalus, Lituites, Lingula, Terebratula, Pentamerus, Orthis, Atrypa, Leptana, Delthyris, Avicula-numerous corals, (Farosites, Catonipora, Cyathophyllum, 8c.,) Tentaculites. An American specimen of a very remarkable shell, Bellerophon dilatatus, (pl. 12, fig. 23, 24, of Murchison,) brought to England" by Mr Featherstonehaugh, which we have seen at the museum of the Geological Society, could not be distinguished, on direct comparison, from specimens found in the Wenlock limestone at Burrington, near Aymestry.

† Annual Reports relative to the Geological Survey of the State of New York, &c., No. 50, January 24, 1840, p. 394-5.

We shall conclude this article by mentioning two points, on which we hope that our wishes may be successful.

1. We earnestly suggest to the author of the volume we have just examined, and would gladly extend our recommendation to M. de Verneuil, whose acquaintance with the fossils of the more ancient strata particularly qualifies him for such an enquiry, not to let another summer pass without examining in person some of the supposed Silurian tracts in North America. 2. We would press upon the attention of British geologists the necessity of making themselves familiar, by personal examination, with the Silurian rocks of England and Wales. They will probably find enough to reward enquiry in the discovery of some new phenomena, and of many details which, with all his diligence and activity, must have eluded the author of the present volume in a region so extensive; and we do not hesitate to propose an invasion also of the Cambrian territory, where Professor Sedgwick's empire has been so long established, that, whenever he publishes a full account of his observations, he can have no rival to fear. But the great benefit resulting from what we recommend, will be, that our practical geologists will thus be enabled to appreciate the comparative works of foreigners, and themselves be qualified to compare with effect the ancient rocks of other countries with

Assuredly no person can henceforth consider himself as acquainted with the geology of England, by whom the Silurian strata have not been studied in the field.

our own.

ART. II.--Patchwork. By CAPTAIN Basil Hall, 3 vols. 8vo.

London : 1841.

CAPTAIN BASIL HALL is an indefatigable writer, and writes

well on whatever subject he undertakes. The volumes which are now before us afford an illustration of this; for we need not go beyond the title-page to be satisfied that we shall find therein something de omnibus rebus. He tells us in his preface, that in propounding the title of his book to his publisher, the latter opposed it stoutly; and even stated, in round terms, that such an appellation would inevitably damn the work ;'-an opinion in which, it seems, several of his literary friends agreed. We have only to say, on our part, that we differ from his friends and his publisher; and we think, moreover, that none but a very surly and caustic critic would quarrel with this title, much less with the material itself, or think of unsheathing his scalping-knife to rip up or damage a splendid piece of Patchwork, composed of lively and well-assorted colours, merely because he disliked the name,

Besides, we think the title appropriate as a pendent to the - Fragments,' recently produced from the same hand, and we believe brought to a profitable market.

If we take the three volumes of Captain Hall in connexion, they may be said to correspond with the title ; but, considered separately, there is something like an unity of subject in each, were it not for the interposition of a few discordant links that break the continuity of the chain; yet even these, by varying the style and tone of the main subject, afford an agreeable variety. Thus, in the midst of some vivid and beautiful descriptions of the Alpine mountains and passes, such as Mont Blanc and the Mer de Glace, two chapters are introduced—the title of the one · The Beginning of Life;' of the other, · The End of • Life’-both of which are of such a character, that, in our opinion, they would much better have been omitted; the one being unsubstantial essence-a mere dream and the other of too dismal a colour to match at all with the rest of the work. Again, in the second volume, which treats mostly of Italy and the Islands of the Mediterranean, the first chapter is entitled “ The Tide Harbour,' certainly as unprepossessing a subject in name as could well be imagined ; and yet, from the great variety and perpetual bustle and change of objects, and of the general scene, it presents a picture full of life and animation; and it is this picture that we propose first to notice.

When the tide is in, and the tide is out, the same harbour, as every one knows, presents a totally different appearance. At high water, says Captain Hall, we behold a beautiful basin, brim full, bearing on its surface numberless vessels, all of whose masts, ropes, and sails, loosed to dry, are reflected in the mirror upon which they rest, so gracefully, that we know not which to admire most, the bold originals, in all their pomp and bustle, or their inverted and softened representations beneath. Then the little boats flitting across the harbour, ships arriving or departingsome dropping anchor with a thundering splash, others laboriously heaving up that ponderous mass of iron-give an endless variety to that busy scene. The cheerful voice of the seamen as they work, and the brawling of the noisy boatmen, have a characteristic and stirring interest. The wharfs and piers are crowded with spectators, some watching the arrival of long-looked for friends, others bidding adieu to those that are departing; while there are knots of idlers, who, having no precise business any where, are attracted merely by the beauty and interest of this

« EelmineJätka »