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tainly that there is no great necessity for endeavoring to esta blish a new one. We therefore conclude, that since most minerals are well defined chemical compounds, they ought, as nearly as possible, to be arranged in the same order as a chemist would class them in his laboratory, and we do not see why, since minerals are the productions of the great laboratory of nature, they should be submitted to what Professor Mohs calls a natural-historical classification.'

The next subject we have to consider is the new nomenclature proposed by the author. We are inclined to object altogether to this wholesale introduction of new names; and if this nomenclature is a necessary consequence of the new classification, it would be alone a sufficient reason, in our opinion, for rejecting the classification. To those who have already learned other names, such an innovation would be an intolerable burden. To those who begin mineralogy, it may be thought as easy to learn one set of names as another: but they must either satisfy themselves to speak a language unintelligible to the majority, if they follow Mr. M., or else they must submit to learn twice as many names as are really neces sary and useful. No possible practical good to mineralogists can arise from a total rejection of the old names; and the only cases where the new might be used are when the chemical composition of the species is sufficiently well established to use the name which chemical nomenclature indicates. Not only, however, do we object to this new nomenclature as a whole, but also as it regards details, It combines a strange mixture of some of the old names, or rather, of the chemical names, with some of the new ones. Thus, augite is called paratomous augite spar; hornblende, hemi-prismatic augite spar. Sometimes, again, the usual names of two distinct species are used to designate a genus: thus we have prismatic talcmica instead of chlorite; rhombohedral talc-mica instead of mica; hemi-prismatic lead-baryte instead of chromate of lead; prismatic sulphur instead of realgar.

We have already stated that most minerals are well-defined chemical compounds. There is already a generally-adopted chemical nomenclature; and, therefore, it is such simple names only as are derived from it which can be allowed to be substituted for the chemical names of minerals.

The author again announces, in the work before us, a separate treatise on crystallography; and, perhaps, before giving any decided judgment on this part of the present work, it would be better to wait for the full developement of that which he intends to publish on this important matter. considerably more than half the first volume is, however, REV. JUNE, 1825.

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entirely devoted to the subject of crystallography, the separate treatise will probably contain little more than the investigations of the formulæ, which are here given without demonstration, and devoid of all the mathematical details. We think we may, therefore, form a tolerably correct notion of the view the author has taken of this interesting part of mineralogy.

Here, too, he has again entirely left the trodden path, in order to newly model the whole fabric of crystallography. The better, however, to satisfy the reader, we will give a short outline of the manner in which he has treated the subject. All crystalline forms, it may be premised, are derived from four distinct fundamental forms, viz. the hexaëdron, or cube; the rhomboëdron; the isosceles four-sided pyramid, or octaëdron with a square base; and the scalene four-sided pyramid, or octaedron with a rhombic base.

Mr. M. at first assumed that the three axes of this last form were always at right angles severally with one another; and his opinion was grounded on a supposition of Haüy, which has been since found to be fallacious. The merit of discovering Haüy's error is, in the preface to the work before us, attributed to Professor Mohs, who does not seem to have detected it farther back than 1822; we believe, however, that the property of the oblique rhombic prism in question, was long before known, in this country, not to hold in every case. However this may have been, the consequence of the fact having become known to Professor Mohs at so late a period is an avowal that the theory of the forms in which one of the axes of the octaëdron with scalene triangular faces is inclined to the other two, or to one of them, has not as yet been perfectly developed.

The author gives geometrical constructions to derive from each of these four forms, series of secondary forms, and explains the notation he uses to designate the relation of any term of each series to the fundamental form. He gives, also, formulæ to calculate the incidences of the faces of the secondary forms, when the law by which they are derived is known: but he does not give the more important formulæ to discover the law from the data of observation.

The whole of this, as an exercise of solid geometry, is uncommonly well done; and might, undoubtedly, when the cases which are not yet perfectly developed shall have been completed, be substituted for what now constitutes crystallography. When, however, we consider that this new method of investigating and describing the relations of crystalline forms does not elucidate any fact which was not already

known,

known, or which might not with at least equal facility be discovered and described by the methods in general use, when we observe that the method of designation is much more complicated and embarrassed than that of Haüy,—we cannot wish for nor recommend the adoption of this new system of crystallography. A person with a competent knowlege of astronomy might amuse himself by writing a book in which all the facts of the science might be expressed by means of co-ordinates different from those which are now generally used to determine the position of a celestial body: but what could be the use or value of such a performance? We look at the crystallographical part of the work of Professor Mohs in precisely the same light. He has expressed the known facts of crystallography in terms derived from his own-created co-ordinates. He has made no mention of the ingenious theory of decrements of Haüy, because natural history does not lead us to inquire into final causes;' nor has he substituted any other in its place. We would not, however, be understood to quarrel with him on this account: yet we think that, as Haüy's theory has been considered so satisfactory by most mineralogists, he ought to have stated the reasons why he would have it altogether abandoned.

As to the details of the work, into the merits of which we have not room here to enter, there are many things which we should be inclined to criticise: such, for instance, as the division made of the felspars, the form given for sulphuret of copper, &c. &c. To discuss separate topics of this sort would take up too much time, and be very likely, at last, uninteresting to most readers. In conclusion, we shall, therefore, only say, the perusal will make it obvious that the work is the result of much labor, that the author and translator are both excellent mineralogists and crystallographers, and the more is it, therefore, to be regretted that so much of their valuable time should have been employed in creating a new language for a science to which they have been such able contributors. The value of their discoveries, we fear, will remain almost unknown till some capable person shall undertake the task of translating them into the usual and general language of the science.

The work, however, as it is, will, as we have before stated, be a desirable addition to the library of those who have already a competent knowledge of mineralogy, and who possess courage enough to study German, or the language of the translator: but we cannot recommend to those who have not yet applied to this science to take up the treatise of Mr. M., for we can anticipate that they will not go far into it if they begin.

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ART. IV. General Zoology; or, Systematic Natural History, commenced by the late George Shaw, M.D. F.R.S., &c. With Plates from the first Authorities and most select Specimens, engraved principally by Mrs. Griffith. Vol. XII. Parts I. and II. Aves, by J. F. Stephens, F.L.S., &c. 8vo. pp. 561. Long, man and Co., &c. 1824.

A CONSIDERABLE interval has elapsed since the publication of the 11th volume of this extensive work; but the 13th is, we understand, in preparation, and will complete the undertaking. The first part of the present is occupied with the Gralla, or Waders, arranged more in conformity with the method of Cuvier, Illiger, or Vieillot, than with that of Linné. Hence, under Tantalus only three species are particularized; namely, Leucocephalus, with a bill upwards of a foot in length; Loculator, peculiar to America; and Ibis, long regarded by naturalists as the sort worshipped by the Egyptians. This last corresponds, however, to Ibis religiosa of Cuvier, and of the writer of this article. Some of the most important observations of Bruce, Savigny, and Cuvier, relative to this subject of classical zoology, might have agreeably enlivened Mr. Stephens's description had they been blended with his very succinct account of the sacred Ibis. The mummies of Ibis ignea, which, from its diversities of coloring, has been multiplied into several species, also occur in the catacombs of Memphis. The social and familiar habits of the Rubra, or Scarlet Ibis, and the circumstance of its shifting its quarters at different periods of the day, are among the topics worthy of record, and calculated to relieve the monotony of a descriptive catalogue.

Numenius here includes several species of the Linnéan Scolopax, or the Curlew tribe, distinguished from the preceding by a more slender bill, rounded in its whole length. — Phæopus, or Whimbrel, comprizes, also, some that were formerly ranged under Scolopax; and the birds pertaining to it have their bills arcuated in the same manner as the Curlews, but rather depressed towards the tip, and having the nostrils in a groove, which extends nearly the whole length of the bill.Falcinellus was instituted by Cuvier, at the expence of Scolopax of Gmelin, Numenius of Latham, and Tringa of Temminck, to comprize the solitary and rare species, denominated Pygmaus, whose summer-plumage is minutely described; but whose winter attire and appropriate habits remain to be determined.

The history of the common Wood-cock is well and pleasingly detailed. To the various particulars stated by the author, he might have added, that the same birds seem to return to the same winter-haunts which they occupied the preceding periodical sojourn. In corroboration of this remark,

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we may mention, that, in the winter of 1797, the gamekeeper of E. Pleydell, Esq., of Whitcombe, in Dorsetshire, brought him, alive and unhurt, a wood-cock which he had caught in a net set for rabbits. Mr. Pleydell marked the date on a small piece of thin brass, which he bent round the bird's leg, and let it fly. Twelve months afterwards, he shot this identical wood-cock, with the brass about its leg, in the very same wood in which it had been caught by the gamekeeper. A second well attested case, is that of a white individual of this species having been seen three successive winters in Penrice Wood, Glamorganshire. It was repeatedly flushed and shot at, during that time, in the very same place where it was first discovered. At last, it was found dead, with several others, which had perished by the severity of the weather, in the winter of 1793. Another, of a slate color, was, some years ago, observed on a particular estate in Ireland for three successive winters, when it was killed by a stranger, who was not aware of the landlord's desire of preserving it. -The apparent incompetency of this bird to sustain a long flight near the earth's surface, and the circumstance of its not ever being picked up at sea in a state of exhaustion, induces the presumption, that it avails itself of currents in the higher regions of the atmosphere for taking its trans-marine flight.

Mr. Stephens includes the Snipe-family under Gallinago, as used both by Ray and Brisson. Of the largest of this species he might have noticed, that it is in some countries a regular, and in others, only a partial migrant; that it resembles in its flight the wood-cock more than the common snipe; and that, on rising, it emits a cry somewhat like that of the latter, but shorter, and of a deeper tone. — Most of our ornithological readers are possibly aware that Dr. Leach had formed a separate genus for the reception of Scolopax grisea of Gmelin, or Totanus Noveboracensis of Sabine, a circumstance which the structure of the bill and of the toes may be supposed to justify: but we could have welcomed some less grating appellation than Macrorhamphus, which the present author has chosen contentedly to adopt in compliment to Dr. Leach. That it is a rare bird, should be asserted with due qualification: for, although it is very seldom found in this island, it abounds in certain districts of the United States. The Cape, the Chinese, and the Madras Snipes, with their varieties, or affiliated species, are referred to Rhynchæa of Cuvier and Horsfield: but the details of their economy are very imperfectly known.

We find the Godwits, or Limose of Cuvier and Temminck, ranking under Fedoa, the term employed by Ray: but, really,

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