Popular Science Monthly/Volume 46/November 1894/Literary Notices

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LITERARY NOTICES.

Collected Essays. By T. H. Huxley. Vol. VI. Hume, with Helps to the Study of Berkeley. Pp. 319. Vol. VII. Man's Place in Nature, and other Anthropological Essays. Pp. 328. Vol. VIII. Discourses, Biological and Geological. Pp. 388. New York: D. Appleton & Co. Price, $1.25 each.

In the preface to the first of these volumes Prof. Huxley repeats his conviction, often expressed, that Descartes, if any one, may claim to be the father of modern philosophy; or that his general scheme of things, his conceptions of scientific method, and of the conditions and limits of certainty are far more essentially and characteristically modern than those of any of his immediate predecessors and successors. A ruling axiom in his work, obedience to which was the source of his great merit — and an axiom which seems, moreover, to have inspired Prof. Huxley in all his studies — was expressed in his famous resolution "to take nothing for truth without clear knowledge that it is such"; "the great practical effect of which," says the author, "is the sanctification of doubt; the recognition that the profession of belief in propositions, of the truth of which there is no sufficient evidence, is immoral; the discrowning of authority as such; the repudiation of the confusion, beloved of sophists of all sorts, between free assent and mere piously gagged dissent; and the admission of the obligation to reconsider even one's axioms on demand." In the reform of philosophy since Descartes, Prof. Huxley thinks he finds the greatest and most fruitful results of the activity of the modern spirit, perhaps the only great and lasting results, in those first presented in the works of Hume and Berkeley, one of whom carried out the Cartesian principle to its logical result, and the other extended the Cartesian criticism to the whole range of propositions commonly "taken for truth." The essay on Hume was prepared originally for the English Men of Letters series, with some hope of passing on to others the benefits the author had received from the study of his works. The author hoped, also, at one time to add an analogous exposition of Berkeley's views, but was unable to carry out his desire, and is forced to content himself with giving two preliminary studies.

The first three essays in Man's Place in Nature recall an incident in the history of science, when, thirty-seven years ago. Prof. Huxley, after due study of the subject, ventured to differ with his fellow zoölogists or anthropologists, and to maintain that so far from certain features of the brain being peculiar to man and separating him far from other mammals, they were shared by him with all the higher and many of the lower apes. The rash philosopher was helped, to some extent, out of the troubles this indiscreet assertion brought upon him by the appearance of Darwin's Origin of Species. In 1860 he delivered six lectures to workingmen on the Relation of Man to the Lower Animals, and the subject was discussed before a "jury of experts" at the Oxford meeting of the British Association; and in 1862 Sir W. Flower publicly demonstrated the existence in apes of those cerebral characters which had been said to be peculiar to man. Besides the three lectures, first published in their present form in 1863, which embody the principles about which controversy raged, the volume contains lectures on the Methods and Results of Ethnology (1865), Some Fixed Points in British Ethnology (1871), and The Aryan Question (1890).

In the third of the volumes the author declares that he has never been able to regard a popular lecture as a mere side-work, unworthy of being ranked among the serious LITERARY NOTICES.

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��forts of a philosopher, and is not one of those " who keep their fame as scientific hiero- phants unsullied by attempts at least of the successful sort to be understanded of the people " ; but has found that the task of put- ting the truths learned in the field, the labo- ratory, and the museum, into language which, " without bating a jot of scientific accuracy," shall be generally intelligible, taxed such sci- entific and literary faculty as he possessed to the uttermost. Yet the popularization of sci- ence has its drawbacks, and success in it has its perils for those who succeed. " The ' peo- ple who fail ' take their revenge, ... by ig- noring all the rest of a man's work and glib- ly labeling him a mere popularizer. If the falsehood were not too glaring, they would say the same of Faraday and Helmholtz and Kelvm." The volume contains eleven lec- tures, among which are some considering the origin and beginnings of life and the date of the beginnings, and involving the questions concerning which the biologists and the physi- cists are at odds. In literary style these es- says are fit to rank among the most vigorous and idiomatic examples of English expres- sion.

A Treatise on Astronomical Spectroscopy. Being a Translation of Die Spectralanalyse der Gestirne. By Prof. Dr. J. Scheixer. Translated, revised, and enlarged by Ed- win Brant Frost. Boston : Ginn & Co. Pp. 482, with Plates. Price, $5.

This book was prepared in the original German because, although the astronomical was one of the most important applications of spectrum analysis, no suitable text-book was found especially devoted to it; the popu- lar works, like Schellen's, admirable as they were within their range, were not suitable for the serious study of the subject, nor adapted as handbooks to scientific investigators ; and while Kayser's Lehrbuch treated the sub- ject in a more scientific way, it dealt with ce- lestial spectroscopy in too brief and incident- al a manner. The author felt, therefore, as the domain of astronomical spectroscopy was widening constantly, an increasing need of a work presenting an exhaustive account of all the modern methods and results of research in this branch of science. For like reasons, and because of the welcome that was given to the book, the translator regarded it as de- sirable that it should be made more available

��for instruction in the higher institutions, and more accessible to English-speaking persons interested in astrophysics. The author has endeavored to satisfy the requirements of both practice and theory, while at the same time giving a record of the results thus far accomplished ; and, to make it more useful for practical work, has added a number of spectroscopic tables and an ample bibliogra- phy. The translator has found the advances in the science during the three years since the original was published so great that much had to be added giving the results of recent observations. As a rule, the portions so add- ed are not distinguished from the original, all that is attempted having been to make the work thoroughly homogeneous and to present the facts and theories as impartially as pos- sible. While this has been done with Prof. Scheiuer's consent, he has opinions of his own on some of the points thus added, which he expresses in the preface. The work is di- vided into four parts, which relate severally to Spectroscopic Apparatus, Spectroscopic Theories, the Results of Spectroscopic Ob- servations, and Spectroscopic Tables.

Great Commanders. General Washington. By General Bradley T. Johnson. New York: D. Appleton & Co. Pp. 338. Price, $1.50.

The author approached the duty of pre- paring this biography for the Great Com- manders Series with much diffidence, because of the multitude of lives of Washington, the industrious authors and translators of which had spared no effort to find all that could be learned about him, so that "no new facts could be adduced to throw light upon his career or his character." Yet he believes that his work is the first attempt to consider the military character of Washington and to write his life as a soldier. While we may admit with General Johnson that the super- human glamour with which a grateful child- nation invested Washington in the years just after the Revolution has fallen away and given place to a more reasonable estimation of him as simply a man of extraordinary virtues, we can not agree with him that any diminution in the general respect for the abihties of the Father of his Country has taken place ; and we can not conceive that he has ever been regarded by the American

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��people as no more than " an honest, well- meaning gentleman, but with no capacity for military and only mediocre ability in civil affairs." His place has never been other than first in the three fields in which the celebrated eulogy gave him that position ; and the steady drift toward giving him his proper place in history and his appropriate appreciation as a soldier and statesman which the author acknowledges to have been going on for twenty-five years, was never less con- stant than it is now. Not words of eulog)', but rational appreciation of facts and calm estimates of deeds and appreciation of the bearing of the statesman's counsels .and words constitute the highest admiration ; and in these the American people have not been wanting toward Washington. In this work General Johnson has made a welcome contri- bution to our knowledge of Washington as he was.

Micro-organisms in Water. Their Signifi- cance, Identification, and Removal. By Percy Fkanklaxd and Mrs. Pkrcy Frankland. New York : Longmans, Green & Co. Pp. 532. Price, $5.

The {)urpose of this work is to present in a compact shape the results of investigation of the bacteriology of water, the literature of which is extensive and very much scattered. The authors have therefore endeavored to present in it in connected form an ac- count of the more important work that has been carried on in this department, in the hope that it may be of service to the student, the investigator, and those who are practically concerned with the hygienic as- pects of water supply. They give, first, a survey of all the more important general methods of bacteriological study, describing in detail those which are specially applicable to the e.\aminati(m of water; second, an ac- count of the principal results hitherto arrived at by the use of these new bacteriological methods in the study of the different kinds of water, and the changes which they under- go through natural and artificial agencies. Particular attention has also been bestowed on the behavior of pathogenic bacteria in water; and a concise description is appended of the principal characters of all the micro- organisms, num))ering more than two hun- dred, which, so far as the authors have been

��able to ascertain, have hitherto been found in water. The first chapter treats of sterili- zation and the preparation of culture media, describing the forms of sterilizing apparatus and the use of them, and giving directions for the preparation of the media, with esti- mates of their value and particular applica- tion. The second chapter is devoted to the staining and microscopic examination of micro-organisms ; the third, to the examina- tion of water for micro-organisms. In the fourth and part of the fifth chapters, account is given of the numbers of micro-organisms that are found in waters derived from different sources, as ice, hail, rain, rivers, lakes, etc. The various methods of purifying water for drinking purposes are described and dis- cussed in the fifth chapter. The subjects of the succeeding chapters are the multiplica- tion of micro-organisms ; the detection of pathogenic bacteria in water ; the vitality of particular pathogenic bacteria in different waters ; the action of light on micro-organ- isms in water and culture mediums; and tabular desciiptions, with illustrations, of the various micro-organisms found in water.

How Gertrude teaches her Children. By JoHANN Heixrich Pestalozzi. Trans- lated by Lucy E. Holland and Francis C. Turner, and edited by Ebenezer Cooke. Syracuse, N. Y. : C. W. Bardeen. Pp. 256. Price, $1.50.

This is described on the title-page as an at- tempt, given in the form of a report to the So- ciety of the Friends of Education at Burgdorf, to help mothers to teach their own children, and an account of the method. But little of it has been translated before, those portions given in Biber's Life of Pestalozzi being, ac- cording to the editor, all. There are difficul- ties in the way of translation, on account of the use of peculiar terms for which there is no adequate English rendering. The trans- lators have tried to give a literal translation without paraphrase and without omissions. They do not regard their work as perfect, and will " gladly and thankfully " receive any help which will make the authors' thought still clearer. The translation is preceded by a biographical and historical introduc- tion. The position of this work is de- fined by the editor as along with the Method and the First Letter from Stanz, the place of the method being after Letter I of this

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��book, in which Pestalozzi gives the history and circumstances that led him to those piinciples which he first definitely stated in the Method. These three essays form a com- plete group, and are estimated as Pestalozzi's most important educational works.

Woolen Spinning. Bv Charles Vickerman. New York : Macmillan & Co. Pp. 352.

This work is designed to be a text-book for students in technical schools and colleges, and for skillful practical men in woolen mills, which the author believes has long been wanted. The want is accentuated by the re- trograde position into which the woolen in- dustry has drifted during late years. The object of the book is to restate the prin- ciples that underlie the various processes and operations of the earlier portions of the woolen manufacture, and to assert their importance from the nature of the material in its raw state onward through every opera- tion up to its being ready for the loom. The special subjects are considered of the nature and qualities of wool, sources of supply, sort- ing, scouring and drying, bleaching and ex- tracting, dyeing, teasing or willeying, burr- ing, mixing, oiling, carding; spinning, its history, principles, and progress ; and the self-actor mule. The text is made clearer by the aid of numerous illustrations.

Bible, Science and Faith. By the Rev. J. A. Zahm. Baltimore: John Murphy & Co. Pp. 316. Price, $1.25.

The purpose of this book is to discuss the relationship between religion and science, and to prove that there is no antagonism be- tween the truths of the Bible and the truths of Nature as revealed by scientific research. Some of the topics treated were presented before the Catholic summer school in 1893, and excited much interest and discussion. The author recognizes that a more extensive acquaintance with the natural and physical sciences, and the accumulation by Egyptolo- gists and Assyriologists of new historical facts of far-reaching importance, have thrown much light on many parts of the Bible that were previously ill understood, if at all, and have supplied us with the necessary data for the solution of numerous perplexing prob- lems -which before were regarded as inex- plicable mysteries. The notion is contra-

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��dieted that reliance upon the Bible as a divinely inspired book should interfere with the freedom of investigation any more than reliance upon the compass or lighthouses should cripple the mariner's freedom of sail- ing. The truths of faith and the truths of science, though belonging to different cate- gories, can never come into conflict. Both have God for their author. Guided by these views, the author discusses the Mosaic Hexa- emeron in the Light of Exegesis and Modern Science (showing in the discussion how St. Gregory of Nyssa foreshadowed the nebular hypothesis and St. Augustine was an evolu- tionist) ; the Noachian Deluge, particularly with reference to its geographical, zoological, and anthropological universality; and the Age of the Human Race according to Mod- ern Science and Biblical Chronology.

The Natural Law of Money. By William Brough. New York: G. P. Putnam's Sons. Pp. 168. Price, $1.

In this work the successive steps in the growth of money are traced from the days of barter to the introduction of the modern clearing house, and monetary principles are examined in their relation to present and past legislation. It is shown in the begin- ning that money came into use on account of its inherent fitness for certain services and men's appreciation of its value for such services before laws were made for its regu- lation and independently of laws. This argu- ment is further developed to show that legal regulation can not, does not, and never did give value to money or affect it in any way save that unwise enactments may limit its elasticity and usefulness. " Clearly there is no need of making coin a legal tender at any weight whatever. If governments would confine their legislation to fixing by enact- ment the fineness of the precious metal and the number of grains that shall constitute each piece of a given size, they may safely leave the maintenance of the coinage in its integrity and the value of the pieces to be regulated by individual interest and action. Practically this point of monetary advance- ment has been reached by most of the civi- lized nations; but in the useless, although comparatively harmless, act of decreeing that coin shall be a legal tender at its bullion worth is manifested the extreme conservatism

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��which still clings to the old delusion that legislation may in some vague sense regulate the value of coin. Although this delusion is harmless, as now exhibited in coinage acts, it becomes extremely mischievous when the attempt is made to regulate the value of the silver and gold coin at a fixed ratio of weights under the ruling of bimetallism ; and it is only in a less degree mischievous when one of the money metals is ejected from the circulation under the ruling of monometal- lism." The argument is further carried out in chapters on Paper Money and Banking ; the Monetary System of Canada; Money, Capital, and Literest ; and Mandatory Money and Free Money; and is enforced by cita- tion of The Hoarding Panic of July, 189S, when business found temporary relief from embarrassment in a method of its own spon- taneous devising independent of legislative enactments.

The Steam Engine and otiter Heat Engines. By J. A. Ewing. New York : Macmillan & Co. Pp. 400. Price, $3.76.

The author of this work is also author of the article on the same subject in the Ency- clopaedia Britannica. Starting to expand that article into a university text-book, the additions and changes became so consider- able that a virtually new work, except for parts of one or two chapters, was the result of the effort. The design has been to treat, besides the thermo-dynamics of the steam en- gine, of other aspects of the subject that ad- mit of theoretical discussion, such as the kine- matics of the slide valve and the kinetics of the governor and of the moving mechanism as a whole, and to give a general, if brief, ac- count of the forms taken by actual engines and of the manner of tiieir working. No at- tempt has been made to describe details par- ticularly, but the distinguishing features of certain types have been indicated. In doing this, the greatest amount of space has been given to the less familiar forms, on the prin- ciple that a student need be at no loss to learn the construction of engines of the commoner kinds. Under " other heat engines " are in- cluded air, gas, and oil engines. The author has endeavored throughout to make evident the bearing of theory on practical issues ; and the experimental study of steam engines is described at some length. In the course of

��the work are reviewed the Early History of the Steam Engine, the Elementary Theory of Heat Engines, the Properties of Steam and the Elementary Theory of the Steam Engine, the Behavior of Steam in the Cylinder, the Testing of Steam Engines, Compound Expan- sion, Valves and Valve Gears, Governing, the Work of the Crank Shaft, Boilers, Forms of the Steam Engine, and air, gas, and oil en- gines.

Papers and Notes on the Glacial Geology OF Great Britain and Ireland. By the late Henry Carvill Lewis, M. A., F. G. S. Edited from his unpublished MSS., with an introduction by Henry W. Crosskey, LL. D., F. G. S. London and New York : Longmuns, Green & Co. Pp. 469.

Had Carvill Lewis lived the ordinary span of life, the problem of the glacial de- posits would have been pushed well toward solution by his efforts. One is fully convinced of this by an examination of the materials and the observations upon them accumu- lated by him which are now given to the public. His energy and ability are evident in his unfinished work, and, being thoroughly acquainted with geological principles and having the means to devote himself to his chosen researches, he would undoubtedly have accomplished important results. His last labors were done upon the glacial de- posits of the British Isles. The whole of Scotland, nearly the whole of Ireland and Wales, and the northern part of England are included in the glaciated area of those islands. The volume before us opens with introductions by Dr. Crosskey and Mrs. Lewis, then follow five papers on various phases of the general subject. The greater part of the volume is made up of Prof. Lewis's field note books, which embody his observations made in the several glaciated counties of England and in L-eland during a visit in 1885 and another in 1886. Some field notes made in Switzerland, Italy, Germany, Bel- gium, and Holland are given in an appendix. From these materials we can derive Lewis's theory of glaciers as it was when his labors ceased. Not all glacialists will agree with it, for there are wide differences of opinion upon glacial theory. There is not even agreement as to matters of observation. But every one must admit that his hypothesis is clear and consistent, and requires no extrava-

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��gant assumptions. It conceives the ancient ice sheet as formed thus : From many groups of mountains there radiate glaciers wliich meet and unite, but do not entirely lose their individualities. Each may be traced in its course by the nature of the stones which it carries, and the furthest advance of each will be marked by a terminal moraine. These glaciers would frequently form lakes by damming rivers, and the lakes would make deposits which must be distinguished from those dropped by the ice. The former he calls bowlder clay and the latter till. Many earlier theories and beliefs are vigorously shaken up in these notes. In the freely ex- pressed opinions jotted down, in its evidence of the forming and abandonment or modifica- tion and development of views, this volume has a peculiar value that a finished treatise would not have. The investigator who would carry this subject forward should read the posthumous contribution of Prof. Lewis care- fully and often.

Essays in Historical Chemistry. By T. E. Thorpe, Sc. D., F. R. S. London and New York: Macmillan&Co. Pp.381. Price,

$2.25.

In the dozen or so of lectures and ad- dresses which Prof. Thorpe has gathered into this volume he tells how most of the great chemical discoveries of the past two hundred and fifty years have been made, and gives us an acquaintance with the per- sonalities of the men who made them. The lectures are arranged in historical sequence, the first sketching the life and work of Rob. ert Boyle, and the others dealing successively with Priestley, Scheele, Cavendish, Lavoisier, Faraday, Graham, Wohler, Dumas, Kopp, and Mendeleeff. In this volume we may read how oxygen and the composition of water were discovered, and what were the re- spective shares of Priestley, Cavendish, and Lavoisier in these discoveries ; how Wohler broke down the barrier between organic and inorganic chemistry, and how the wonderful Russian, Mendeleeff, evolved the periodic arrangement of the elements. We may, moreover, learn also that Cavendish was in- tensely shy, a hater of noise and bustle, and had a house made up of laboratories and workshops, very little of it being set apart for personal comfort ; that when young Fara-

��day was traveling on the Continent as aman- uensis to Sir Humphry Davy he wrote of Lady Davy, " Her temper makes it oftentimes go wrong with me, with herself, and with Sir Humphry," and similar interesting facts about the other men included in the volume. The lectures have been delivered as occasion has called them forth, to a variety of audi- ences, and the author is far from claiming that they constitute a history of the time from Boyle to the present day.

An Introduction to the Study of Society. By Albion W. Small, Ph. D., and George E. Vincent. American Book Company. Pp. 384. Price, $1.80.

The inquiry for a syllabus of sociological method printed in 1889 by one of the au- thors of this manual furnished surprising evidence of demand for scientific exposition of social relations. The interest in philosoph- ical sociology has continued to increase in this country. Since the organization of the Department of Sociology in the University of Chicago applications for information about a suitable text-book of the subject have been incessant. No such text-book existing, this manual has been prepared as a guide to the elementary study. It does not presume to be a contribution to sociological knowledge or a report of research on the material of social knowledge, but a help in the training of beginners, the proposal of a method of preliminary investigation, a "laboratory guide " ; the outgrowth of experience in teaching sociology under difficulties. It aims to commend a method that shall emphasize the necessity of precise knowledge of social facts, and shall confirm students in the habit of widening their comprehension of particu- lars by relating them to the containing con- ditions. The first book, on the Origin and Scope of Sociology, starts with the begin- nings of the science, and goes on to treat of its development, its relation to the special social sciences and to social reforms, and of the organic conception of sociology. The second book, on the Natural History of a Society, takes the family, composed of the man and his newly married wife going to open a farm and settle on the native, solitary prairie, and traces the gradual growth of the community through the increase of the family, the accession of new settlers, the beginning of

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��local trade, the constitution of the village and its development by the organization and di- vision of industries, the establishment of com- munications, the formation of various social groups, and all the processes of commercial and municipal growth into the town and the city. The third book concerns social anat- omy and the analysis of the elements and factors in the development described in the preceding book ; the fourth book, the physi- ology and pathology of society ; and the fifth book, its psychology. The essay is illustrated by five maps and charts delineating the sev- eral stages of the growth of the social organi- zation.

Progress in Flying Machines. By 0. Cha- NUTE, C. E. The American Engineer and Railroad Journal, 47 Cedar Street, New York. Pp. 308. Price, $2.50.

The subject of aerial navigation has be- come quite prominent of late by reason of important advances in this field that have been made during the past few years. The idea of controlling the course of a great bag of gas through the currents of the atmos- phere has been well-nigh abandoned, and reliance is being placed more and more upon mechanical motors, the buoyancy of the air as exerted under large horizontal surfaces, and the force of the wind. Flying machines are now deemed much more practicable than dirigi))le balloons. Mr. Chanute's book con- sists of a scries of illustrated articles contrib- uted to The Railroad and Engineering Jour- nal, the chief aims of which were to show whether or not man-flight is possible ; to save waste of effort on the part of experimenters by making known what forms of apparatus have failed ; and to enable investigators to judge as to whether new machines that may be proposed in future are worthy of trial. The author divides flying machines into three classes : (a) Wings and parachutes ; {h) screws to lift and propel ; (c) aeroplanes. Flapping wings in imitation of those of birds were eariy tried, and Mr. Chaaute describes many curious forms of them, the earliest authen- ticated proposal being credited to Leonardo da Vinci. The first known proposal for an aiirial screw was also his. Aeroplanes, how- ever, do not date back much before the mid- dle of the present century. Like the first- mentioned class of machmes, their principle

��is derived from an action of birds in this case the soaring or sailing action. Most of the flying machines described are shown in simple drawings. The results attained by Maxim, Lilienthal, and other recent expeii- menters are given, the book having been held back from the binder to append Lilienthal's own account of his latest work.

Six General Laws of Nature (a Ne^o Idealism) is a compendium, by Solomon J. Silberstein, of a large work which he con- templates publishing, on Divinity and the Cosmos. It is intended to contain " the primitive cause of force and matter, an ex- planation of all the physical phenomena in the actuality of the universe, and an attack on the modern scientists and philosophers." The author has satisfied himself by careful analysis that all the systems of philosophy are incomplete, unsatisfactory, and insuffi- cient to the deep, logical, and honest thinker, and that most of the laws or axioms in mod- ern natural science are very often defective, and even false. He therefore issues this work in correction of these errors, with the arguments and demonstrations through which he believes he has discovered the mystery and explained the physical phenomena of Nature.

The fields of biology and physics meet in the Investiffations on Microscopic Foams and on Protoplasm., by Prof. 0. Biitschli, of Heidelberg, which has recently appeared in an English translation (A. & C. Black, Lon- don, $6.25). Protoplasm is conceived of in this work as having the structure of a froth or foam in which minute droplets of a watery liquid take the place of air in the bubbles of an ordinary foam. The author has carefully investigated this structure in an effort to throw light upon the physical conditions of the phenomena of life. He has imitated it in oil foams and studied the phenomena of these, and has also investigated the structure of protoplasm in various organisms. About half the work is devoted to a summary of the views of other investigators upon the structure of protoplasm. The volume con- tains a list of works referred to, an index, twelve lithographic plates, and a number of figures in the text.

In preparing a series of essays on TTie de- lation of Biology to Geological Investigation

�� � (United States National Museum), Dr. Charles A. White had in view, among several objects, a further presentation of elementary matter pertaining to biological geology than has heretofore been published, the defense of biology as an indispensable aid in geological investigation, the repudiation of certain untenable claims that have been made in its favor, an application of the principles discussed to the practical work of the geologist, and the demonstration of the necessity of the preservation of fossil remains in public museums as storehouses of evidence upon geological questions.

How to Build Dynamo-Electric Machinery, by Edward Trevert, is intended to be a practical treatise, and in no way to be considered technical. Some theory, however, is given to help the reader in a general way. Its purpose is to give directions for building small dynamos and motors, accompanied by working drawings which will enable the reader to understand the text more clearly. The machines described have been carefully selected for efficiency and beauty of form and as being easy to build. Chapters on commercial dynamos and motors are added to show the general construction of large machines; and chapters on management, armature winding, and field-magnet winding, and a chapter of useful tables are inserted. The machines described are all American. (Published by the Bubier Publishing Company, Lynn, Mass. Price, $2.50.)

In Hydraulic Power and Hydraulic Machinery (J. B. Lippincott Co., American publishers) Henry Robinson has drawn from his own practice and utilized the experience of others, as reported in the proceedings of various professional societies, to record, in a form convenient for reference, existing experience in the engineering of water-pressure machinery. Special attention is given to the subject of the flow of water under pressure and to the employment of water-pressure mains to transmit power through the streets of a town on the principle which the author terms "power co-operation." Since the first edition was published, in 1886, the author has had constantly in view the desirability of enlarging and improving it. The present, second, edition is the outcome of this desire and contains much new matter, with better treatment of the old. Some compression, both of subjects and of descriptions, has been necessary to accomplish this, but the author thinks the illustrations selected of the innumerable applications of hydraulic power will be considered fairly to meet the circumstances.