Page images
PDF
EPUB

people ; but, in what he has done, he has been actuated solely by the love of truth and the desire of rendering justice to his subject.

MINERALOGY. Art. 32. Elements of Crystallography, after the Method of Haüy;

with, or without, Series of Geometrical Models, both solid and dissected, exhibiting the forms of Crystals, their Geometrical Structure, Dissections, and general Laws, according to which the immense Variety of actually existing Crystals are produced. By Frederick Accum, Operative Chemist, Lecturer on Practical Chemistry, on Mineralogy, and on Chemistry applied to the Arts and Manufactures; Member of the Royal Irish Academy, Fellow

of the Linnæan Society, &c. With Copper-plates. 8vo. . pp. 454. 165. Boards. Longman and Co. 1813

As every man of science, who is desirous of becoming acquainted with the curious and recondite laws of mineral crystallization, will naturally resort to the original writings of Romé de Lisle and of the Abbé Haüy, the present elementary treatise, which is illustrated by a great variety of diagrams, and by the more tangible expedient of wooden models, is chiefly calculated to accommodate those students who are little conversant in the French language, or in the principles of geometry. A detailed analysis of its contents would scarcely be intelligible without the figures; would require much more room than we can spare ; and would, at best, exhibit only the sketch of a system which is now generally understood by professed mineralogists, and the merits and defects of which we have, in the course of various articles, endeavoured to appreciate.

Mr. Accum's original design is well conceived, and the execution of it will furnish considerable facilities to the apprehensions of the English tyro in mineralogy : but a somewhat more methodical arrangement of his materials, a reduction of the size of his type, the suppression of one set of voluminous contents, the retrenchment of a few irrelevant sections, and, above all, a due degree of respect to accurate printing and to the first principles of English grammar, would have enabled us to report the result of his labours in terms of more unqualified approbation. For a work which has the slightest pretensions to science, the list of acknowleged errata is sufficiently numerous : but various slips and inaccuracies remain to be corrected. We find, for example, parallix for parallax, noxius for nonius, enduced for endued, is a polygon for in, arrangement are, an extreme mechanical divisions and suspensions, solutions which yields, the principal angle are, the three first sections which there present itself, with several incomplete sentences, &c. &c. Gahn, the Swede, is styled a German philosopher; and the theory of crystallization is said to have been created by Haüy, as if Linne, Bergmann, and Romé de Lisle had never meditated on the subject. — Again, the non-crystallization of basalt ought not to be gratuitously assumed, especially in a publication destined to state the leading facts and first principles of a science. The varieties and irregularities exhibited by columnar basalt arc by no means irreconcileable to the crystallizing process; which, from various disturbing causes, or from the nature and proportions of the composing ingredients, is liable to deviations from the strictness of form. Such deviations, in prismatic basalt, scarcely detract from the general aspect of its regularity, which some of the most ingenious observers of nature have not hesitated to ascribe to crystallization, properly so called. Nay, they have even applied the term basalt, or the expression basaltic crystals, to mineral substances of which the forms are usually prismatical. Thus, Linné, Cronstedt, Wallerius, De Born, and Kirwan, include under basalt all the varieties of schorl, cross-stone, tourmaline, &c., which nobody presumes to exclude from the list of crystals ; though few of them occur with configurations as neat and decided as those of basaltic columns. Romé de Lisle himself, yielding to the influence of evidence, had comprehended the latter in his essay on crystallography : but, perceiving that their anomalies occasionally infringed on the geome. trical precision of his system, he had afterward recourse to a sort of intermediate mode of aggregation, removed both from confused mixture and from chemical crystallization : so that, according to his theory, the prismatic forms of basalt, their plane faces, and sharp angles, (prolonged, sometimes without apparent defect, to the height of fifty feet,) thousands of columns, of equal dimensions, and of which by far the majority present the same number of faces, are merely the effect of irregular shrinking. As the polygonal forms, however, which the portions of fused metals assume in cooling, are also induced by shrinking, (that is to say, by a more or less regular approximation of their particles,) and as this operation of nature is, without challenge, denominated crystallization, the doctrine involves a distinction of terms without a difference. Several observations of Dolomieu and Ferber lead to s'inilar conclusions : but we cannot here prosecute the argument at greater length.

The production of wood-stone, by the substitution of the particles of mineral for those of vegetable matter, is in like manner open 'to controversy; and, though honoured with the suffrage of the Abbé Haüy, it appears to be pressed with very formidable difficulties. Thus, trunks of trees, from 20 to 40 feet in length, which are buried at a small depth from the surface, in sandy beds, are, from the bark to the very core, converted into siliceous matter ; though the sand which is in immediate contact with them, on every side, in no degree participates of the converting influence. Now, we cannot easily conceive that the liquid, which held in solution the stony matter that is supposed to have assumed the place of the woody particles, should not have agglutinated, and converted into quartzose sand-stone the sand which immediately surrounds the petrified wood. With respect to the ligneous organization, which the advocates for substitu. tion conceive to be destroyed, we may observe that not only the most minute fibres have perfectly preserved the form and situation which they manifest in the fresh state of the wood, but even all their appropriate shades of colouring. If, therefore, the stony had taken the place of the ligneous particles, the whole petrified mass would have been of an uniform colour; since the same stony matter would have successively filled all the vacancies occasioned by the retreat of

the

the ligneous particles. Besides, if we carefully examine the state of this description of petrified wood, we can perceive no symptom of previous decomposition. Some specimens exhibit not only the most entire organization, with the shades of each fibre, but worms which are themselves converted into agate ; with their external surface whitish and opaque, and their interior characterized by waving zones, of different tints, which appear to represent their intestines. The annual circles of the wood, and the medullary prolongations from the centre to the circumference, are distinctly traceable ; and it is par. ticularly worthy of remark that, in these and similar specimens, the only unsilicified parts are precisely those which had suffered decomposition. In the cabinet of M. Le Camus, are specimens of agatized wood, found at Naufle, near Grignon, which contain a multitude of the larvæ of insects, retaining their natural form. In others, the worms are observed to be moveable in their cavities, a circumstance irreconcileable with the infiltration of a quartzose fluid, which would have consolidated the mass. Saussure quotes a fossil crab, of which even the ova under the tail are petrified. These and other facts, which might be mentioned, would induce us to believe that the siliceous petrifaction in question is effected very rapidly, and seem to exclude all idea of decomposition and the tardy process of successive substitutions ; because, from the moment in which soft bodies, like maggots or worms, are affected by putrefaction, their forms can no longer be preserved.

Still, after all the exceptions which even the rigour of criticism may make to the merits of the present performance, we may safely recommend it as an useful and popular introduction to the science of crystallography. The models, to which the text refers, may be procured either directly from the author, or through the medium of the booksellers.

SINGLE SERMON. . Art. 33. On the Causes and Remedy of Schism. By L. Blakeney,

A.M., Curate of Thorndon and Bedingfield, Suffolk. 4to. 28. Wilson. 1813.

The Bishop of Norwich, to whom this sermon is dedicated, must have been amused by Mr. Blakeney's curious mode of disappointing the critics, who, he concludes, will expect adulation in the address of a curate to a bishop. In the very act of disclaiming all flattery, he overwhelms the R.R. prelate with a dose of it that is sufficient to make a vain man sick, and then slyly hints at the difference between a cure and a benefice. In this way, he deceives the critic's foresight! If his reasoning in the sermon does not succeed better than his cunning in the dedication, he will not come off with very Aying colours. We must tell Mr. B., in limine, that, for a Protestant clergyman, Schism is a very difficult corpse to bury; and that, unless by the attempt he can change a cure into a benefice, he had much better let it alone : since, while he himself claims the right of protesting against the church of Rome, his brother-protestants will assert the same right of protesting against his church ; and if he should lament to the Catholic

priest,

priest the growth of schism, the priest would turn short and charge him with being the cause of that evil of which he complains. 'Mr.B. is fully aware of the consequences of diffused knowlege, and deprecates the employment of persecution in order to produce uniformity of opinion, or the external appearance of it : but he does not seem to be sufficiently enlightened respecting the real sources of dissent from the Established Church. It is ridiculous to attribute the diversity of religious opinions in the Christian world to the love of novelty; or to imagine that those, who object to the doctrines of the 39 Articles, can be induced to forsake the conventicle by an eulogy on the sublimity of the Liturgy. As Mr. B. cannot or will not see the true causes of separation, or schism, he is not qualified for prescribing a remedy. Much, therefore, as we applaud the liberality of some of his remarks, we cannot think that his discourse is on the whole likely to produce any good effect.

CORRESPONDENCE. The Rev. W. Lisle Bowles, whose Sonnets and other poetical works are well known, has avowed himself to us as the author of the poem intitled the Missionary, on which we bestowed merited commendation in our Number for April last; and at the same time he informs us that a new and corrected edition of it will appear in the course of this year, the favor of the public having disposed of the first impression.

P. T. of Birmingham will have the goodness to summon a little patience to his aid. He is perhaps very little aware of the multitude of publications which claim notice in our pages. If he will vigilantly keep a list of all the new works which issue from the press in the course of six months, before he writes another poem, he will have some idea of the nature of the case, and will give us time to read and review that which he has written..

which he has written.

[ocr errors]

.

.

.

We do not yet know what reply to make to Inquisitor : but we will consider the matter to which he refers.

S. R. arrived too late for present consideration.

In some copies of the Review for May, an error appears in the substitution of the name Menelaus for Manalus, in page 3. line 9. from the bottom, and p. 14. 1. 8. from the bottom.

** The APPENDIX to Vol. lxxiii, of the M. R. was published on the ist of June, with the Number for May. . .....

THE MONTHLY REVIEW,

For JULY, 1814.

Art. I. The Character of Moses established for Veracity as an

Historian, recording Events from the Creation to the Deluge. By the Rev. Joseph Townsend, M.A., Rector of Pewsey, Wilts. 4to. pp. 454. With twenty-one Plates. 31. 35. Boards. Long

man and Co. 1813. W ITH unusual form, this volume is ushered into public notice

" by two Introductions. In the first, we are apprized that the work is the result of half a century of travel and geological research, of extensive and appropriate reading, and of personal intercourse with some of the most eminent surveyors of rocks, mountains, and strata ; and, in the second, we are rea minded of the dissonant sentiments of Cudworth and Huet with respect to the identity of Hermes and Moses." ** . We are next presented with two chapters, the first of which treats of the genuineness of the Pentateuch; and the second, of the credibility of the Mosaic history, deduced from internal and external evidence. In these, however, we can discern neither novelty nor ingenuity of argumentation; nor can we refrain from intimating a suspicion, that the pious author has made a toilsome but fruitless parade of learning and philosophy. That certain trains of events are recorded in our sacred books cannot be called in question; and that the occurrence of them, combined with subsequent traditions, ought to have convinced the Jews that the events themselves were accomplished by the immediate interposition of Heaven, will Scarcely admit of discussion : but the sceptic of the present dáy may call for proofs of the alleged miraculous facts, or of the inspiration of the books in which they are recorded. If either of these points could be satisfactorily established, no candid inquirer could impeach the veracity of Moses as an historian : if, for example, he has furnished us with a transcript of real occurrences, we can obtain no more powerful evidence of divine agency; or, if it can be demonstrated that his narratives were dictated by the superintending influence of. Deity, . the niost pertinacious dogmatist must yield assent to their truth, VOL. LXXIV.

however

« PreviousContinue »