DANA'S SYSTEM OF MINERALOGY." As the previous edition of this standard work was exhausted eight years ago, a re-issue has long been anxiously anticipated. Indeed, there is so deplorable a poverty of mineralogical literature in the English language, that the student can ill afford that any work of value should remain inaccessible. The failing health of Dr. Dana, coupled with a desire on his part to introduce certain improvements into the present edition, has tended to delay the publication from time to time. At length, however, with the co-operation of Professor Brush, he is enabled to give us the long-expected volume. On opening the book-a bulky octavo of nearly 900 closelyprinted pages-one feels somewhat disappointed to find that, with the exception of about fifty pages of introductory matter, the present edition embraces only the descriptive portion which formed the second volume of the earlier work. Although the preface is silent on this point, we understand that the author proposes to issue a new edition of his first volume in the shape of an independent treatise. Among the many improvements noticeable in the volume before us, we may especially allude to the introduction of a system of historical synonymy, a feature which greatly enhances the value of the work, since it forms a guide in tracing the history of any given species. The consultation of original authorities for these synonyms must have involved a considerable amount of literary research. This research has led the author to a revision of our mineralogical nomenclature, by which he attempts to recognize, as far as possible, the law of priority in selection of names. This has of course necessitated the revival of many obsolete names, whilst an attempt to secure uniformity of nomenclature has led to the introduction of many new ones. Thus, for example, Rock Salt is described under the new name of Halite, whilst Zinc-blende is to be found under Glocker's old name of Sphalerite. In other cases, the terms are only modified by altering their terminations into ite, and in this way we get such names as Galenite, Pyrrhotite, Castorite, &c. Again, Kupfernickel is termed Niccolite, and our hybrid adjective nickeliferous assumes the more consistent latinized form of niccoliferous. Indeed "nickeliferous" is not a better word than copperiferous." Nevertheless it is doubtful whether such innovations will hold their ground, in spite of their introduction under the prestige of so respected an authority as our author. *A System of Mineralogy: Descriptive Mineralogy, comprising the most recent Discoveries.' By James Dwight Dana, aided by George Jarvis Brush. 5th edition. 8vo. New York, 1868. For an exposition of Dana's views on 'Nomenclature,' see ' Quarterly Journal of Science,' Jan., 1868, p. 105. Writing at a time when chemistry is verging on a new phase, Dana very prudently effects a compromise between the new and the old theories by writing his formulæ in accordance with both. Another improvement in the present edition is the systematic recognition of the varieties of each species. Although Professor Brush's name appears on the title-page of this edition, it would seem that his labours relate only to the pyrognostic characters of the minerals described. "Neither the consultation of original authorities, the drawing of conclusions, nor the putting of the results on paper, has been delegated to another. And being now," continues the author, "but half-way between the fifties and sixties, it is my hope that the future will afford another opportunity for similar work." In this hope, every mineralogist will heartily concur. ENGINEERING WORKS. A TREATISE on Coast Defence,' by Von Scheliha, LieutenantColonel and Chief Engineer of the department of the Gulf of Mexico, of the army of the late Confederate States of America,* deserves more than a passing notice, containing as it does a very comprehensive account of the means for the attack and defence of coasts, as practised in modern warfare, backed by the experience gained during the late American war. Thus it forms a very valuable addition to works on Military Engineering, and will doubtless be found a useful text-book for the study of naval and military officers. It will readily be admitted that the progress made in naval architecture, and in artillery, necessitates some modification of the principles heretofore observed in coast-defence. The increased power of the guns of the present day would knock to pieces any fort that was constructed twenty or even ten years ago, and the masonry walls of recent years must now give place to iron sheathing. Wherever practicable, a well-turfed earthen slope is, however, still a safe protection in many cases; but the recent invention of Lieutenant Moncrieff's elevating gun-carriage will, if found practicable in service, go far towards inverting the present practice of coast-defence, and pits will be dug for the guns instead of building forts; thus they would be entirely protected from all, except shells, and no doubt means will soon be devised for keeping them out also. In the work under our notice the advantages of railroad communication along the sea-shore are forcibly pointed out as a means whereby the scattering of forces by fortifying places of secondary importance may be avoided; on this point there can be *London: E. & F. N. Spon, 1868. no manner of doubt, but efficient training of a military railway staff would in all cases be desirable, and the railway itself should, as far as possible, be concealed or otherwise out of range of the attacking force, forming, as it were, a covered way of communication between the principal points of defence. The effects of bombardments which took place during the American war on the different kinds of forts has furnished materials for a chapter on the relative advantages of masonry, earth, and sand works, as a means of protection against modern artillery. The disadvantage at which all forts stand before modern armourclad fleets leads to a discussion of the necessity of blocking up the channels by which they may be approached, either by sunken or floating obstructions, or by torpedoes of various descriptions; the former preventing the too near approach of hostile vessels, and sometimes holding them in check at a point where they may be exposed to a cross-fire from masked batteries, whilst torpedoes are calculated to disable a vessel at once, and so place it at the mercy of the defenders. A considerable portion of the work is given to the consideration of this kind of obstructive defence, and in it is embodied much useful information on that point. The subject of lighting up channels has also engaged the author's attention. This may be turned to account, either for peaceful or hostile purposes, and if properly illuminated it would be impossible for a hostile crew to approach unseen within certain limits of the shore. Throughout, the work is liberally illustrated, and altogether forms a handsome, as well as very instructive volume. Mr. Latimer Clark has recently given us 'An Elementary Treatise on Electrical Measurement for the use of Telegraph Inspectors and Operators.'* The author of this work is sufficiently well known as one of our leading telegraph engineers, to stamp any work emanating from his pen with a degree of authority, but unfortunately, for want of proper proof corrections, one or two grave mistakes occur in the formulæ, which will, however, doubtless be corrected in a future edition; as they are palpably merely typographical errors, we refrain from noticing them here more particularly. This volume is a work quite different from any book hitherto published on electrical subjects, and it contains a mass of useful and practical information relating to electrical tests, as well as the various properties of the materials used in telegraphy. It is doubtful whether it will ever become popular amongst casual students of electrical science, but it was clearly not written with that view; to those, however, who follow telegraphy as a profession, its value will no doubt be fully appreciated. * London: E. & F. N. Spon, 1868. Theoretical Astronomy, relating to the motions of the heavenly bodies, &c., embracing a systematic derivation of the formula for the calculation of the geocentric and heliocentric places, for the determination of the orbits of planets and comets, for the correction of approximate elements, and for the computation of special perturbations; together with the theory of the combination of observations, and the method of least squares, with numerical examples and auxiliary tables. By James C. Watson. Royal 8vo, cloth, pp. 662. Philadelphia, 1868. Trübner and Co. This is a useful treatise, going over the same ground as Chauvenet's valuable Treatise on Astronomy. The latter work is, however, the more complete. We notice also some pages in Mr. Watson's work which require revision. On the whole, however, and considering the extent and difficulty of the subjects treated of, his work is a meritorious one. Celestial Objects for Common Telescopes. By the Rev. T. W. Webb, M.A., F.R.A.S., Incumbent of Hardwick, Herefordshire. Second edition, revised and enlarged. Longmans. We are glad to see a new edition of Mr. Webb's valuable treatise. As a convenient text-book for the advanced amateur observer, this work is likely to hold its ground for many years. In the new edition Mr. Webb has availed himself of the advice and experience of our leading astronomers. He is himself also in the front rank among observers, a circumstance which largely enhances the value of his work. His treatise is especially valuable for those who wish to take part in the investigation of the moon's surface. We notice a new appendix, in which all the chief lunar objects are arranged alphabetically. There are also two other new appendices; one containing a list of objects in the southern hemisphere, the other giving in their order of right ascension all the stars referred to in the body of the work. There are also one or two new illustrations in the present edition. Altogether the work is one which we can cordially recommend to all those who wish to become systematic observers of the heavens. THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. MEETING AT NORWICH, AUGUST, 1868. THE PRESIDENT'S ADDRESS. DR. HOOKER referred at the commencement of his address to his own early career, which began thirty years since at the Meeting of the British Association at Newcastle. It was to his voyage then undertaken, in company with Sir James Ross, in the Antarctic seas, that his position as President on that evening, he felt, was due. He had not been able to find time to survey the rise of scientific Botany in this address, nor to discuss the relation of the allied sciences to Botany, as he had wished, but he proposed to touch on various matters which appeared to be of interest at the present time. First of all, it was necessary to introduce the International Congress of Pre-historic Archæology, who were to hold their meetings at the same time as those of the British Association. Sir John Lubbock was to preside over this meeting, and it would, Dr. Hooker hoped, receive the cordial sympathy and support of the scientific men then in Norwich. An important matter connected with the science of man had been lately under the consideration of the Council of the Association itself, which must interest equally the members of the Congress. This was the investigation of the habits, manners, form, &c., of the indigenous populations of India, especially those which erect megalithic monuments. In consequence of representations from the Council, the Government of India had set to work to obtain photographs and other information in regard to these people. "It will, no doubt," said Dr. Hooker, "surprise many here to be told that there exists within 300 miles of the British capital of India, a tribe of semi-savages which habitually erects dolmens, menhirs, cysts, and cromlechs, almost as gigantic in their proportions, and very similar in appearance and construction, to the so-called Druidical remains of Western Europe; and what is still more curious, though described and figured nearly a quarter of a century ago by Col. Yule, the eminent oriental geographer, except by Sir John Lubbock they are scarely alluded to in the modern literature of pre-historic monuments. In the 'Bengal Asiatic Journal' for 1844, you will find Col. Yule's description of the Khasia people of East Bengal, an Indo-Chinese race, who keep cattle but drink no |