Descriptive Catalogue of Photographs of North-American Indians. By W. H. JACKSON. Washington: Government PrintingOffice.

THE collection of photographs of members of different NorthAmerican tribes, formed under the auspices of the United States Geological Survey of the Territories, is an ethnological monument of peculiar value. It embraces over one thousand negatives, representing no fewer than twenty-five distinct tribes. Of these not a few are in process of extinction, whilst the rest are undergoing a process of intermixture with each other, and with the different nationalities of European or African origin who have overspread the western hemisphere. Hence a collection like the one in question is necessarily unique, and if it should. be allowed to perish could never be reproduced. The catalogue is arranged ethnologically, and includes a short history of each tribe.

The Scientific Basis of Music. By W. H. STONE, M.A., M.B. Oxon, F.R.C.P., Lecturer on Physics at St. Thomas's Hospital, Vice-President of the Physical Society. 71 pp. London: Novello, Ewer, and Co.

THIS little book is one of a series of "Music Primers" issued by the above enterprising publishers. Although intended as manuals of instruction for beginners, they are so carefully written, and so much above the ordinary run of books-good, bad, and indifferent-which we meet with as tutors and instructors in various branches of music, that they can be read with interest even by advanced students, and, as far as they go, are worthy to take rank with some of the admirable works published under the auspices of the Paris Conservatoire. Dr. Stone's work treats on a department hitherto much neglected by the musical student: the author-himself a good practical musician, as well as a physicist is admirably qualified for the task he has undertaken.

In the first chapter the sources of sound are fully and clearly explained. At page 21 the author mentions the class of Membranous Reeds, such as the larynx and the human lip acting on the cupped mouthpiece of a brass instrument: the author defers the consideration of the subject to a future chapter, but careful reading fails to find any further mention of this interesting class. of sound-producers; it is to be hoped that this defect may be remedied in a future edition.

The following chapters explain the subjects of Velocity, Reflection, Refraction, Interference, Tonometry; Musical Tone,

Harmonics, Consonance, Quality; Concord and Discord, and Resultant Tones.

The last chapter, on Scale and Temperament, gives an account of several contrivances, all more or less elaborate, having for their object the perfect tuning of keyed instruments. It is to be feared that these complex key-boards offer such obstacles to freedom of execution as to be useless for all practical purposes. Dr. Stone's remarks on tuning an orchestra are admirable, and will be read to advantage by every instrumentalist, many of whom, as conductors know too well, are extremely loose in their ideas of accuracy.

A page at the end of the little book is devoted to the bibliography of the subject, and will greatly aid the student in extending his researches.

Studies in Spectrum Analysis. By J. NORMAN LOCKYER, F.R.S. Second Edition. London: C. Kegan Paul and Co., 1, Paternoster Row. 1878.

MR. NORMAN LOCKYER'S present volume forms part of Messrs. Paul's excellent International Scientific Series, and is written for the perusal of the more serious portion of the reading public, as well as for the more purely scientific student. Beginning with the vibrations of a jerked rope, the author explains, in a singularly clear and homely manner, the phenomena connected with wave-motion, the illustrations employed by him being of a nature which will be understood by every observant person. He shows that the principles upon which all undulations are produced -whether they are caused by muscular force, sound, heat, light or electricity are similar, if not identical, a point which is only too frequently lost sight of by writers and lecturers on popular science. If, by setting forth the relationship between a note in music and a bright line in the spectrum, a thoughtful reader or lecturer can by analogy be made to see how the effects of a change in the rate of the wave-motion of the luminiferous ether as affecting colours are brought about, a great point is gained. We believe Prof. Barrett, in his lectures on the Connection between Light and Sound, was one of the first to break ground in this direction: and the fact that light is nothing more than an excessively fine kind of sound, the effects of which were perceived by the eye instead of the ear, was a revelation to the majority of his hearers. Mr. Lockyer treats of sound, light, heat, and electricity concurrently as being parts of one grand system of wave-motion, and we should be pleased to see his example followed by writers on elementary science who only are too fond of separating these subjects by hard-and-fast line s instead of treating them correlatively.

The present work may be said to be in some sort the complement of Mr. Lockyer's former work on "The Spectroscope and its Variations," seeing that it goes much more deeply into the theoretical part of this subject. The subject of wave-motion having been explained, the author next describes the principal methods of demonstrating spectral phenomena, and the value and use of the photographic camera in their registration.

The fourth chapter, in which atoms and molecules are treated of in relation to the spectroscope, contains a large amount of theoretical speculation of a very interesting character; and the same may be said of the chapter on Dissociation, in which Mr. Lockyer boldly attacks the integrity of certain of the elements, such as calcium and hydrogen. Mr. Lockyer's speculations in this direction are of a most suggestive kind, and ought to form the starting-points for a large amount of investigation. If our present elements are ever to be split up, either theoretically or practically, the spectroscope will have undoubtedly commenced the work.

The account given of Messrs. Lockyer and Roberts's experiments on the quantitative analysis of gold and other alloys show that one of these days the spectroscope will play an important part in the assay of the precious metals. The results given by these experiments are of a very promising nature, and it is only the close attention which Mr. Lockyer has to give to the more important branches of Spectroscopy that prevents him and his colleague from bringing their researches to a thoroughly practical termination. By the present method an assay takes at least two hours, whereas by the use of the spectroscope it might be performed in a few minutes.

The book is well illustrated by eight photo-lithographic plates of spectra and fifty well-executed woodcuts.

Industrial Chemistry. A Manual for Use in Technical Colleges and Schools, and for Manufacturers, &c. Based upon a Translation, partly by Dr. T. D. BARRY, of Stohmann and Engler's German Edition of Payen's "Précis de Chimie Industrielle." Edited throughout, and supplemented with Chapters on the Chemistry of the Metals, &c., by B. H. PAUL, Ph.D. Illustrated with 668 Engravings on Wood. London: Longmans and Co. 1878.

AFTER a very attentive examination of this, the most recent contribution to the literature of Industrial Chemistry, we must confess that we are utterly puzzled to discover for whose benefit this book has been compiled. Judging from the title-page and preface, it is not only intended for manufacturers and technolo

gical students, but for schoolboys and the general public as well. Now, if it is intended for the first-mentioned category of readers, it is at once too copious and too meagre, teaching those things it ought not to teach, and leaving untaught those things it ought to teach; if for the latter, it is again far too detailed in some parts and too superficial in others. The great mistake committed by the whole of the five writers connected with the work has been in endeavouring to teach too many things at once, the consequence being that the book is overloaded with instructions in the rudiments of chemical science, and descriptions of elements and compounds that have nothing to do with Industrial Chemistry. The natural result of this waste of space is that hosts of important compounds, whose names have long been household words even amongst the general public, are either passed over in silence or dismissed in a few lines. Will it be credited that in a work published in the last quarter of the nineteenth century, and written "for manufacturers, &c."-while page after page is devoted to lengthy descriptions of such rarely seen elements as tellurium, gallium, yttrium, and a dozen others, half a page is given to platinum as an industrial metal, and such everyday products as dynamite and carbolic acid are barely mentioned. Had the space occupied by so much useless and extraneous matter, all of which may be found in any half-crown Manual of Chemistry, been devoted to the real object of the work, we might possibly have had a few pages given to such minor matters as calico-printing, aniline, anthracen and naphthalin dyes, collodion, Esparto grass, pebble powder, oxalic acid and its salts, tannic and pyrogallic acid, picric acid, and other chemical pro. ducts which are constantly mentioned in the columns of every newspaper.

The way in which the translation is executed and edited leaves much to be desired; but the portions added to Messrs. Stohmann and Engler's adaptation of Payen's "Précis," which are evidently from the practised pen of Dr. Paul, form a strong contrast, in the ease and completeness with which they are written, to the disjointed style of the remainder of the work. The additions, in fact, are the best part of the book, which is more than half again as large as Stohmann and Engler's translation.

The work is ostensibly intended for English use, but in many parts too much favour has been shown to foreign processes to the entire exclusion of the methods of working usually adopted in this country. For instance, although Weldon's chlorine process is fairly described, Spence's improvements in the manufacture of alum and Mactear's method of sulphur recovery are entirely ignored. These are only two out of the many English processes which have been passed over in silence.

Another singular defect, which ought not to exist in a book of this sort, is the almost entire absence of references to fuller accounts of processes than the space at the editors' disposal

would allow them to give-a fault that is also to be found in the German and French editions.

It is with great regret that we feel called upon to be so severe upon a work which has appeared with so many well and favourably known names attached to it. Such a book-we mean a manual of technological chemistry in the fullest sense of the term-is much wanted, but it must consist of many volumes, and be written and edited by more than one man. A book on industrial chemistry in a single volume is of but little use to the manufacturer or the technological student. A popular account of the more striking improvements which have lately taken place in chemical manufactures, treated in a lively style, and a plainly written manual of chemistry applied to the arts, for the use of schoolboys who have already gained some knowledge of the science, are both loudly called for, but Drs. Paul and Barry's compilation satisfies none of these requirements. It is also to be regretted that the beautiful copper plate engravings of the French and German editions have been replaced by small wood

cuts.

Metals and their Chief Industrial Applications. By CHARLES R. Alder Wright, D.Sc., &c. London: Macmillan and Co. 1878.

THIS book contains the substance, with several valuable additions, of the course of lectures on this subject delivered by Dr. Wright, last year, at the Royal Institution. The author has the gift of conveying a large amount of practical information in a few words, without, however, falling into the sin of dryness. The lectures are avowedly popular; theory, therefore, receives comparatively little attention. The principles, however, upon which different ores are made to yield up their metals are clearly and succinctly explained. Dr. Wright has brought his information down to the very latest date, and the processes of Siemens, Bessemer, and other modern workers in the field of metallurgy are fully described. As an instance of the author's conscientiousness in this respect it may be mentioned that Allen's nickel process, described in the "Journal of the Society of Arts" of so late a date as last February, is to be found in its proper place.

For a young student desirous of gaining a general insight into metallurgical processes there could hardly be a better manual. The book is well illustrated; and although it seems ungracious to find fault where there is so much to praise, we must remind Dr. Wright that an Index is an essential part of such a work.