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patient training" which follow. We would like to know the technique of the operation, and the name of the operator and that of the institution where he operates. Some grown persons might desire to secure his services, and almost everybody could point out some one else, to whom they think such a course of treatment would be useful. Some peculiar conditions might be found which it would be desirable to remove permanently, and so save the “labor of long years" etc.

The editor of the Journal on page 609 stimulates our curiosity further by saying that “Professor Elmer Gates, a psychologist who has for several years been making elaborate studies both in Washington and Philadelphia, has added not a little to our knowledge of the developments of the brain and the relation of particular parts of the brain to thought and emotion and the use of particular parts of the body.” The view indeed is not new, but the confirmation given by Prof. Gates researches is very interesting” He then quotes language from Dr. Julius Althaus as to the supposed seat of mental activity in the brain, which embodies a general statement of the little knowledge we have on the subject. The question naturally arises as to the alleged researches of Dr. Gates, and the extent to which they have confirmed our hypotheses on this subject, and if so, as to where they were published ? The editor does not tell us. This is a pity, for assertions without authority are useless to science. Is there any connection between these researches and the alleged vivisection of idiots recounted in the article we first quoted ? The name signed to the latter is not that of Dr. Gates, so we are quite in the dark. A journal which publishes an article by Sir Wm. Dawson, and writes up the Universities, ought to give us more light no these wonderful researches.

-It is again proposed that the American Association for the Advancement of Science meet in San Francisco in the near future. The Board of Supervisors of that city are said to have extended an invitation to visit the city in 1897. The Association has had many such invitations, and they would have been accepted had the railroad authorities been willing to place their rates within reach of the members. The authorities of San Francisco have, however, this time included in their invitation the British and Australian Associations, and we are informed that the British members will have free or nominal transportation via the Canadian Pacific R. R. It is said that the Dominion of Canada will make an appropriation towards defraying their transportation expenses. Perhaps our Congress would be willing to make an appropriation for securing the transportation of our own members. The amount will not exceed the outlay on funeral solemnities annually expended by it. Such meetings tend to bring about amicable relations among the living, and to promote the interest in and distribution of knowledge. It might be good politics if the Canadian Boundary and Venezuelan questions should be still on hand in 1897.

RECENT LITERATURE.

Petrology for Students: An Introduction to the Study of Rocks under the Microscope, by Alfred Harker, University Press, Cambridge. MacMillan & Co., New York, 1895. Pp. vi and 306; figs. 75; price $2.00.

This volume of the Cambridge Natural Science Manuals will be heartily welcomed by teachers and students of geology in all Englishspeaking countries. It presupposes a knowledge of the microscopical features of minerals, and consequently deals only with rocks. These the author divides into Plutonic, Intrusive, Volcanic and Sedimentary rocks. Under each head the general characteristics distinguishing each of the several rock classes are briefly mentioned, and descriptions of the different rock types embraced in each group are given. First come descriptions of the constituents of each rock, then follows a statement of its pecularities of structure. The principal varieties are next mentioned, and abnormal, structural and chemical forms are briefly described. The book concludes with chapters on thermal and dynamic metamorphism and one on the crystalline schists.

Of course, the treatment of the different subjects discussed is necessarily very brief, nevertheless it is full enough in most cases to give the student beginning petrography a very good view of the field. A spe. cially important feature of the work is the large list of references to articles written in English. With this book at hand, students will no longer be required to wait until they have mastered German before beginning the study as heretofore been the case. While by no means exhaustive, the present volume will serve as an excellent introduction to the larger French and German treatises, and will, at the same time, be a good reference book for geologists who do not desire to make a specialty of microscopic lithology.-W. S. B.

Crystallography, a Treatise on the Morphology of Crys. tals, by N. Story-Maskelyne, Oxford, Clarendon Press, 1895. New York : MacMillan & Co. Pp. xii and 512 ; figs. 597, pl. viii; price, $3.50.

This “Crystallography” is a real addition to the literature of the subject that it treats. Its appearance reminds one strongly of Groth’s

Physiographische Krystallographie," although the book is by no means a reproduction of the German treatise. The latter discusses the subject from the side of solid symmetry, whereas the former deals with it rather from the analytical point of view. The first 187 pages of the volume treat of the general relations of crystal planes and of zones. The next 200 pages take up the six crystal systems beginning with the cubic, and discuss in order the holosymmetrical and the merosymmetrical forms, combination of forms and twinned forms. Chapter VIII, embracing pages 388–463, is devoted to crystal measurements and calculations, and the final chapter to the projection and drawing of crystals. The plates show the projection of the poles of the most general form and of its derived hemihedral and tetartohedral forms in each system.

It is almost needless to state that the work of the author is based exclusively on the system of indices, known generally as the Miller system. Not only are the faces of crystal forms studied through the aid of the spherical projection, but the individual planes are discussed solely in terms of their normals. No reference is made to other systems of notation, nor to other methods of projection than those elaborated. The book might have been of a little more practical value had the author at least referred to other systems, but its unity might have suffered. As it is, the volume is a very complete exposition of crystallography from the Miller standpoint, and it will, without doubt, prove of inestimable value in popularizing this—the most beautiful method of studying the subject. Of course, the treatment is purely mathematical, but the mathematics used are simple enough to be understood by any one acquainted with the methods of spherical geometry. To the student of minerals too much emphasis will seem to be placed on the theoretical aspect of the development of crystal forms, but to the specialist in crystallography, the emphasis will appear to be placed just where it belongs-on the possibility of deriving all possible symmetrical polyhedrons from certain simple abstract notions concerning pairs of planes, at the basis of which is the principle of the rationality of the indices.

There is no doubt that the treatise before us will appeal less strongly to the student of forms than it will to one of analytical proclivities. Nevertheless it is needed even by the former, if, for no other reason, because it will impress him more strongly than ever with the exactness with which nature constructs her inorganic structures. With Dr. Williams' little book to develop the imagination of the beginner in crystallography and to interest him in the science, and the present volume to carry him on to a very thorough understanding of the relationships of crystal forms, the English-reading student-world is as well, if not as bountifully, supplied with text books on the subject as are the students of any European country.

The authors discussions are all logically developed, and all his statements are clear and simple. The figures are well drawn and the subjects they illustrate are well selected.-W. S. B.

Elementary Physical Geography, by Ralph S. Tarr. New York: MacMillan & Co., 1895. Pp. xxxi and 488; figs. 267, plates and maps 29; price $1.40.

The most striking features of Prof. Tarr's book are the freshness and wealth of its illustrations and the excellence of its typography. The volume is just what its title indicates, except that perhaps the treatment of its subject matter is a little more inclined toward the side of physiography than toward physical geography. The book is indeed elementary-more so than one would wish, sometimes; at other times it is elementary in the statement of the facts described, while leaving their causes unexplained, where a word or two might have avoided a difficulty which the teacher will surely meet with in discussions with his brightest scholars. In the arrangement of material, some fault can easily be found, but, as the author himself declares, the treatment is, "in many respects, experimental.” In spite of these criticisms, the experiment is a success.

The volume is divided into three parts, with four appendices and a very good index. The first part deals with the air. It includes chapters on the earth as a planet, the atmosphere in general, distribution of temperature in the atmosphere, its general circulation, storms, its moisture, weather and climate, and the geographic distribution of plants and animals. Why the first and last chapters included in this part are discussed here is not quite plain. Part second deals with the ocean. It embraces chapters on the ocean in general, waves and currents and tides. Part third treats of the land and its features. A general description of the earth's crust is discussed in the opening chapters. Then follow chapters on denudation, the topographic features of the surface, river valleys, deltas, waterfalls, lakes, etc., glaciers, the coast line, plateaus and mountains, volcanoes, earthquakes, etc., man and nature and economic products. The appendices include one on meteorological instruments, methods, etc., one on maps and one containing suggestions to teachers. The last is a list of questions on the text. At the end of each chapter is a list of reference books, with their titles and prices. This is not of much value to the student, but is convenient for the teacher. A list of articles to be found in Nature, Science, the Popular Science Monthly, and similar periodicals might have been of more value in an elementary treatise. However, the plan of referring students to original articles on the subjects discussed is commendable. We can not dismiss the book without another reference to the many really excellent illustrations and charts it contains. The former are, without exception, fresh and new, well chosen to illustrate the author's points and well executed from the bookmaker's standpoint. Many of the charts are original. The volume is, on the whole, the most attractive that we have seen on the subject it treats, and its attractiveness is not at the expense of scientific accuracy. We can safely predict a general adoption of the book as a text in many high schools and academies, and we shall be mistaken if it is not used in some of our colleges, where the instructor desires an aid in his work rather than a substitute for work.-W. S. B.

Gray's Synoptical Flora of North America.-In 1835 or 1836, Dr. John Torrey planned a Flora of North America, with which Dr. Gray soon became identified, and, in July, 1838, the first part (Ranunculaceæ to Caryophyllacex) was published; a little later (October, of the same year), the second part appeared, and in June, 1810, the third and fourth parts were issued, completing Vol. I, the Polypetalæ. As will be remembered, Volume II was not completed, a portion appearing in 1841, and the work being suspended at the end of the Coni positæ in 1843 (February). Here the work stopped for many years, and was resumed in 1878 by Dr. Gray (Dr. Torrey having died five years earlier) under the slightly different title of A Synoptical Flora of North America. In this volume the Gamopetale were completed; in 1884, the Compositæ and preceding families, since whose elaboration more than forty years bad passed, were revived. Then shortly afterwards, 1888, came the death of Dr. Gray, followed, in 1892, by the death of Dr. Watson, before the publication of other parts.

In October, 1895, Dr. B. L. Robinson issued the first fascicle of the revision of Vol. I of the Flora, a little more than fifty-seven years since the appearance of the corresponding fascicle. This includes the polypetalous families-Ranunculaceae to Frankeniaceae. It includes much

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