plants have been long cultivated without change; others show a manifest tendency to vary. In some cases these changes are induced by simply sowing the seeds in highly cultivated soil, while in others there is need of artificial fertilizing. This fertilization has not been effected between different species, as is too often supposed, but between half-breds, i.e., between different varieties of the same species. All individuals thus obtained will breed to any extent. There has been a too ready admission of so-called new species. If all the pretended novelties were carefully examined, the number of the species would be reduced by one-half or more, as would also the genera. This excessive multiplication of species is well seen in such genera as Rubus and Hieracium. In Linnæus's time there were two species of brambles, Rubus fruticosus, and R. cesius. But of these Grenier and Godron have made 22 species; Boreau has made 54, and a German bramblemonger called Müller has made 238. The species of Hieracium have been so multiplied, that they can only be distinguished by the names or numbers stuck at their sides in herbaria or botanic gardens. If these names or numbers happen to be lost, it is in inost cases quite impossible to identify such species, the trifling characters of which can only be compared to those of the persons who established them. Some idea may be formed of the confusion that at presents exists in this genus, when we recollect that the Hieracium murorum and sylvaticum of authors have naturally brought forth 60 new species. The true observer of nature will bring these varieties within the compass of the species to which they rightfully belong. These variations of species are limited. They have a certain range beyond which they do not extend. Cultivated varieties, when left to grow wild, return to the original stock whence they came. Darwin has not disproved this by his statements. Neither the vegetation of the present day nor that of bygone epochs of the world's history support his views as to the origin of species. He cannot produce intermediate transition forms, even with the help of countless ages of geological formations. Dr Bree thinks that in every great period of geological history, the world has been peopled by creatures adapted to its physical and climatic condition, and that there is no evidence to show that this has not been done by distinct acts of special creation, by Him whose wisdom our finite minds are too apt to interpret and criticise.

The denial of per saltum changes seems to savour much of the views of the scoffers mentioned by St Peter, who thought that all things had gone on from the beginning without catastrophes of any kind, and who did not believe that the present world was to be finally burnt up and a new earth formed. Darwin assumes that " no cataclysm has desolated the whole world, and that we may look with some confidence to a secure future of equally in

appreciable length," in which, "judging from the past, we may infer safely that not one living species will transmit its unaltered likeness to a distant futurity." On the dogma, natura non facit saltum, Dr Bree makes some valuable remarks; and in pages 52 to 61 he gives a graphic and amusing description of the appearance of various organic tribes on the earth when viewed from Darwin's stand-point. In this sketch he attempts to bring out the fallacies of the system, and the crudeness and untenableness of the theory.

Another point on which Dr Bree dwells, is the implied imperfection of organic beings as regards their functions, and the necessity for a gradual improvement by their own efforts. While Darwin speaks of instinct and adaptation as being at first imperfect, and as being gradually improved by individual selection, Dr Bree shows that, as regards the instincts of animals, the formation of the various organs, the minute structure of the body, and the microscopical character of the fluids-all is adjusted in a most perfect and complete manner, indicating creative design and not mere chance variations by natural selection, as it is called.

Dr Bree treats the subject in a clear, distinct, and popular manner, and brings strong arguments of his own and of others to bear on Mr Darwin's theory. We recommend the book to the perusal of all who take an interest in natural science.

Geological Treatise on the District of Cleveland, in North Yorkshire; its Ferruginous Deposits, Lias, and Oolites; with some Observations on Ironstone Mining. By JOSEPH BEWICK, author of "Remarks on the Ore and Ironstone of Rosedale Abbey." 8vo, pp. 194. London: Weale. Newcastle: Reid. 1861.

In these times of neck-and-neck competitions in commercial enterprise, and hand-to-hand conflicts for political ascendency, wherein the ingenuity of man is taxed to the very confines of his intellectual as well as of his physical capabilities, whether for the attainment of individual prosperity or for the gratification of national ambition,-a question of no mean importance suggests itself as to the durability of the resources at his command in the one case, and, in the other, of their superiority both in kind and degree over those of his antagonists. The political importance of a nation, it may be assumed, depends less upon the numerical strength of her forces per se, than upon the extent of her natural resources, and the amount of fertilizing genius which she can command to operate economically upon them; and, in truth, she

owes her supremacy not more to the strategic qualifications of her generals than to the patient investigations of her philosophers. What proportion the mineral products of this country bear to the sum of its wealth it is not easy to divine. Agriculture in its progress has denuded the surface of its wood; science in return has discovered a wealth of coal and iron. Railways and shipping draw largely on both of these; and, if we mistake not, the latter will make a still greater demand on the iron field when—as we undoubtedly shall have to do-we change the time-honoured epithet of our national bulwarks, and call them no longer our "wooden but our "iron walls." However fascinating may be the pursuit of the speculative science of geology through the fiercely contested theories of the Neptunists and Plutonists, or through the still more remote doctrines of the ancient Greeks and Romans, back even to very chaos itself; it has yet another function, and one of far greater practical utility, by which, in the capacity of pioneer, it guides our labours in the useful and decorative arts; pointing here to marble or granite for the sculptor, there to materials for the builder; and again, directing the engineer or the miner-thereby subordinating external nature, and adapting her more closely to the moral, intellectual, and physical condition of the great human family.

These somewhat disconnected but pertinent reflections have been suggested by the title of the book before us. Before proceeding to remark on the merits of the work, however, it will be important to the reader to have a more accurate knowledge of the geographical position of the district treated of than the author has deemed necessary to supply. Cleveland, Ord tells us, forms part of the North Riding of Yorkshire, and is "bounded towards the north by the Tees and German Ocean; by Mulgrave Castle and Thordisa on the east; by Grosmont Bridge, part of Wheledale Moor, Skinner Howe, Rolles Cross, and Westerdale to the south; then ascending the summits of Ingleby, Broughton, Carlton Banks, and Arncliffe, it includes Appleton-upon-Wick as an extreme boundary on the west. It is forty miles long and eighteen broad." From the chain of lofty cliffs forming its limits at the German Ocean to its opposite boundary, this tract of land presents a series of peculiar and characteristic features, the most prominent of which are those "immense ranges of majestic hills," of which the author treats. The contrast of its wild and wide-spread moors, with its nooks of verdant pasturage; its dales, its rivers, and its woods, render this locality a pleasant retreat to every lover of the beauties and sublimity of nature.

The work we speak of is divided into six distinct parts or treatises, of which the first and second comprehend a geological delineation of the district, the former describing the consecutive strata of the formation, the latter having particular reference to

the ironstone seams. In the third treatise the author gives a practical explication of ironstone mining as pursued in the mines under his own direction, together with some remarks on the necessity of a careful and thorough ventilation. The fourth section contains some practical suggestions for the improvement of the port and harbour of Whitby. Fifthly, we have a paper on the coal deposits. Sixthly, a brief paper on the "probability of reaching the Coal-measures under the Lias and other formations in North Yorkshire and Cleveland." And, lastly, a short appendix containing a "tabular synopsis of the strata forming the Oolitic and Lias groups in the vales of Eskdale, Goathland, Newtondale, and Pickering." Hereafter we may perhaps take occasion to offer some remarks upon the purely scientific part of the work, but at present we confine ourselves to the subject in its practical bearing, which is undoubtedly one of great national importance. The ironstone of Cleveland (originally Cliffland) had for many years been known to the ironmasters in the north, but owing to some mismanagement in selecting the specimen cargoes despatched for their approval, its value was not duly appreciated; and it was not until the year 1837 that it met with favourable acceptance. In 1839, Mr Bewick was called to Grosmont for the purpose of conducting the mining operations about to be commenced by Mrs Clark in her own estate. At the same period the "Whitby Stone Company" sunk their first shaft, likewise at Grosmont, whence the mineral was transmitted by the Whitby and Pickering Railway" one of the early undertakings of the elder and illustrious Stephenson" to the port of Whitby. The cautious manner in which Stephenson gave his evidence before the House, when questioned as to the probable speed of his locomotive, is worthy of remembrance by all who are connected with new undertakings; and, indeed, the absence of such caution on the part of the author of "Cleveland" might have been productive of serious consequences.

"After having completed our arrangements for a supply, the managing partner of the firm expressed a hope that we had not undertaken to supply a quantity of ironstone we were unable to work-viz., 10,000 tons per annum; in answer to which we observed that, before the year was over, we had little doubt of being able to raise three or four times that quantity. The observation thus made subjected us to a severe rebuke from that gentleman, accompanied by a well-intentioned admonition, to the effect that nothing was more disadvantageous to a young man than to make unguarded and exaggerated statements. We endeavoured to assure him that there was, we believed, no exaggeration in the statement we had made, in proof of which we had only to mention further that we had ascertained, from careful experiments, that two seams of ironstone in Mrs Clark's royalty

would produce the unheard of quantity of 20,000 tons per acre. This announcement appeared only to make things worse, and he expressed very grave doubts of our being able to fulfil even the engagement we had entered into, being apparently convinced that we were wrong in our calculations, and were labouring under a false impression."-p. 20.

The correctness of his estimate, however, was subsequently placed beyond doubt; for, in 1846, he says-"This contract increased Mrs Clark's vend to 30,000 tons per annum."

The prosperous state to which the iron trade had attained in 1840-41 was followed, in 1842-3, by a more than corresponding depression, when pig iron was quoted so low as 35s. per ton. This, together with the discovery of the "Black Band" in Scotland nearly drove the Cleveland mineral out of the market. By mutual agreement, shipments were suspended at Whitby for two years, after which the iron trade revived, the Black Band disappointed many who had speculated largely in it, and Cleveland ironstone was again in demand. In 1844-5 pig iron was quoted at £6 per ton, and from that time until now the shipments from Whitby have been very considerable. Cleveland stone is not used alone, as it has been found to produce "what is termed, cold, short iron,―viz., iron wanting toughness; which fault is corrected by an admixture of hematite ore, obtained from Cumberland, a comparatively small proportion of which suffices."

The annual produce of the three mines at Grosmont is nearly as follows:

The development of the ironstone workings at Grosmont is checked by the difficulties of transit to the furnaces; the only method of effecting this at present being by means of small vessels sailing from Whitby; and the author does not hesitate to say, that if the harbour were improved, so as to admit a larger class of shipping, the annual production of ironstone at Grosmont would reach ten times its present amount. A line of railway (the North Yorkshire and Cleveland), which is now in process of construction through the very centre of the iron districts of Cleveland will, it is anticipated, very shortly connect Grosmont with the northern coal-fields; and other arrangements contemplated by the North Eastern Railway Company will materially facilitate mining operations throughout the entire locality, The author, however, attaches great importance to improvements in Whitby harbour.