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THURSDAY, NOVEMBER 3, 1904.

APPLIED ELECTRICITY.

(1) Wireless Telegraphy. By C. H. Sewall. Pp. 229.
(London: Crosby Lockwood and Son, 1903.) Price
10s. 6d. net.

(2) Electricity in Agriculture and Horticulture. By
Prof. S. Lemström. Pp. iv +72. (London: The
Electrician Printing and Publishing Co., Ltd., 1904.)
(3) Modern Electric Practice. Vol. iv. Edited by
Magnus Maclean. Pp. viii+ 304.
(London: The
Gresham Publishing Co., 1904.)
(4) The Theory of the Lead Accumulator. By F.
Dolezalek. Translated by C. L. von Ende. Pp.
xii +241. (New York: John Wiley and Sons;
London: Chapman and Hall, Ltd., 1904.)
10s. 6d. net.

Price

(5) Electric Motors. By H. M. Hobart. Pp. x+458. (London: Whittaker and Co., 1904.) Price 12s. 6d.

net.

(6) Notices sur l'Électricité.

By A. Cornu. Pp. vii+ 274. (Paris: Gauthier-Villars, 1904.) Price 5

francs.

(7) L'Année Technique (1902-1903). By A. Da Cunha. Pp. 303. (Paris: Librairie Gauthier-Villars, 1903.) Price 3.50 francs.

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LTHOUGH wireless telegraphy is of such recent development, it is apparently regarded by many as a legitimate subject for historical writing. The first volume before us is one of several which have appeared in the last three or four years in which the historical progress of wireless telegraphy is dealt with rather than its scientific principles. The book possesses to our mind the same faults which characterise all the other similar publications which we have read; there is a Jack of discrimination in the selection of material hich is likely to leave the untechnical reader in a state of considerable confusion. Wireless telegraphy as we know it to-day is wholly concerned with Hertzian wave telegraphy, and even if accounts of the experiments of Lindsay and others in telegraphy by earth or water conduction should be regarded as legitimate, we

cannot see by what possible stretch of the imagination the achievements of, say, Marconi can be traced back to the prophecies of Galileo in 1632.

Mr. Sewall's method of compiling history appears to consist chiefly in making extracts from patents. Page after page of the book before us contains nothing more than reprints from the patents of Lodge, Marconi, Fessenden, and others, sometimes verbatim in inverted commas, at others with slightly altered context as original matter. We imagine it must be easier to write books in this way than it is interesting to read them. Mr. Sewall would have been much better advised, we. think, to digest his material properly and present it to his readers in some more acceptable form. He could then have given a connected account of the remarkable developments that have followed the discoveries of Maxwell and Hertz which would have been of great practical use to students of the subject. At present we doubt if his book is intelligible to the amateur or useful to the expert.

(2) The late Prof. S. Lemström occupied himself for many years with experiments on the effect of electricity on growing plants, and this little book contains the results of his work. If the conclusions at which the author arrives are confirmed by the work of other investigators, the subject is one which merits the most careful consideration by all agriculturists. Practically only one type of experiment was tried; an influence machine was connected with one pole to earth and the other to a wire network over a field in which the crops were being grown. A discharge current could thus be passed either from the network to earth or vice versa for any desired number of hours a day. The experiments were tried on a comparatively large scale in several different localities. The effect produced by this treatment was remarkable. There was an average excess of the crop of the experimental field over that of a control field of 45 per cent.; the excess varies considerably with the nature of the crop and the conditions, soil, weather, &c. Not only is this increase in quantity produced, but there is also often an improvement in quality and a diminution in the time taken for the plants to mature. This last is a factor often of great importance to the grower,

who can realise much higher prices by selling early in the season. Prof. Lemström calculated that in the case of wheat the outlay on a field of 25 acres will be repaid in two or three years, and that afterwards a net profit of 40l. a year or more can be realised. We cannot here enter into the details of the working, such as the best time of electrification, the effect of wet and dry weather, and so forth, but we should strongly advise those interested in the subject to study this book carefully; they will find it full of valuable suggestions, and the time spent in reading it will be amply repaid.

(3) We have already reviewed the first three volumes of this publication, so that it is only necessary here to refer briefly to the matter contained in the present volume. This is devoted to electric tramways, and is divided into seven chapters, dealing with overhead construction, feeders, surface contact systems, conduit systems, rolling stock, electric boats and motor cars, and electric traction on railways. The defects to which we alluded in our previous review are not so noticeable in this volume, which furnishes a good description of a very important branch of electrical engineering. The excellence of the illustrations is a characteristic of the whole production, and is a particularly valuable feature in the present instance, as the subjects are such that they cannot be effectually described without numerous photographs and diagrams. (4) This exceedingly interesting monograph on the much debated theory of the chemical reactions taking place in the lead accumulator is probably already well known in the original German to those who have concerned themselves specially with this subject. Since the book first appeared the discussion has progressed a stage further, so that the English translation may be said to be out of date to a certain extent. This is, however, the penalty that the average English student has to pay for the neglect of his schoolmasters to teach him German, and he will probably therefore welcome the appearance of an English translation. Herr Dolezalek treats the subject from the standpoint of Nernst's osmotic theory, and shows that thermochemical considerations all point to the validity of the sulphate theory originally advanced by Gladstone and Tribe. Whether the author will succeed in satisfying others to the same extent as he has apparently satisfied himself may be regarded as open to question, but in any case the book is one which cannot be neglected by anyone wishing to study this complicated but fascinating problem.

The book is divided into two parts, the first dealing with continuous and the second with alternating current motors. The relative advantages of different types are considered in detail, and there are numerous calculations of motors of different types and capacities. In addition, there are a large number of curves, diagrams, and photographs.

(6) The essays which are comprised in M. Cornu's little book were written with a special and rather peculiar object, the author having been requested by some of his old pupils, who had been unable to keep touch with the rapid development of electrical engineering, to write for them something which would enable them to appreciate better the technical or semi-technical literature of to-day. These "Notices" are consequently of a somewhat elementary character, nor can the book be regarded in any sense as a text-book of electricity. But M. Cornu has succeeded in writing a book which should appeal to a very much larger audience than that for which it was originally intended; one cannot look through its pages without realising at every point that it is the work of a master, and such works repay study by all-the most advanced as well as the most elementary students. The beginner will find here ideas expressed clearly and concisely, and cannot fail to derive great benefit from the book as an introduction to more detailed treatises. The engineer will see well known facts expressed in new and suggestive language, and will doubtless have his own views enlarged in consequence. The subjects dealt with are the correlation of the phenomena of static and dynamic electricity, generators, transmission of power and polyphase currents, and we would strongly recommend anyone interested in any of these matters to spend a few hours reading M. Cornu's admirable booklet.

(7) We cannot help being conscious that the end of 1904 is rather late in the day to review a book which contains a résumé of the technical achievements of 1903. Still, as we gather that this publication is intended to appear annually, this notice may be of some service in directing readers' attention to the volume dealing with this year's progress, which we imagine will appear very soon; in addition, it may be pleaded that the lapse of time enables one to see matters more in the right perspective, and so to form a better estimate of the value of M. Da Cunha's work. The book ranges over a great variety of subjects. Thus we find at one place a mathematical calculation of the (5) The design and construction of electric motors mechanical problems involved in "looping the loop," is becoming daily a matter of more importance to and in another a discussion of alcoholism and temperelectrical engineers on account of the very rapid ance worthy of the columns of a daily paper in the extension of the use of electricity for power purposes. silly season. Between these extremes lie such subjects When one considers the enormous number of tramcars, as the progress in wireless telegraphy, automobilism, lifts, factories, &c., which are driven by electricity, it aërial navigation, and the hundred and one other is easy to see not only how important the subject is, but technical developments which are taking place in all also how very varied is the work which the electric branches of applied science. To the engineer the book motor is called upon to perform. If the development can serve no other purpose than to while away an idle now is great, in a few years' time, when some of the hour or so. The general reader who is interested in numerous power schemes are more matured, it will be scientific and technical progress may read it with both much greater still. The student of electrical engineer-profit and pleasure. He will find the descriptions clear, ing may find here ample scope for his abilities, and he the style agreeable, and the illustrations and diagrams cannot consult a better guide than the volume before us. in many cases excellent. M. S.

ADOLESCENCE.

Adolescence: its Psychology and its Relations to
Physiology, Anthropology, Sociology, Sex, Crime,
Religion. By G. Stanley Hall, Ph.D., LL.D.,
President of Clark University and Professor of
Psychology and Pedagogy. Vol. i., pp. xx+589;
vol. ii., pp. vi+784. (New York: D. Appleton and
Co., 1904.) Price 31s. 6d. net.

THIS
THIS work is one of wide-reaching scope and
interest. The subject of human growth has
already been studied in relation to the earlier years
and in its special features. The period intervening
between childhood and adult life, which has been com-
paratively neglected, is the one to which Dr. Hall has
directed his investigation. The work is thus of interest
in focussing attention on an important section of
human life; it is of value also in that the results of
biology and anthropology are freely used in supple-
menting and interpreting the data which are gained
from physiological and psychological investigation.

practical interests are closely blended. Underlying the scientific treatment there may be said to be two leading principles. One principle is that of the intimate union, or rather the identity, of physiological and psychological processes.

"More summarily, then," he says, "the idea of soul we hold to is in its lower stages indistinguishable from that of life, and so far in a sense we revert to Aristotle, in holding that any truly scientific psychology must be first of all biological. . . . The first chapter of a scientific psychology, then, is metabolic and nutritive, and the first function of the soul is in food getting, assimilation, and dissimilation."

The other principle, of greater novelty and interest, is the application of the recapitulation theory to the mental as well as the bodily life of childhood and youth.

recapitulation theory in the biologic field, I am now "Realising the limitations and qualifications of the convinced that its psychogenetic applications have a method of their own, and although the time has not yet come when any formulation of these can have much value, I have done the best with each instance as it

arose.

The first three chapters deal mainly with physical growth, taking up in order the increase in height and In his application of this theory Dr. Hall is unweight, the growth of parts and organs, and the doubtedly original, but it is strange that among the growth in muscular power. The next two chapters many references to the literature of the subject there deal with the physical and mental disorders of should be no mention of the work of Baldwin on adolescence, and with juvenile faults and immorality." Mental Development in the Child and the Race," in Sex is taken up in three chapters, one relating to boys which the same theory is applied in detail. and two to girls; of these two chapters one deals with the physiology of sex, the other with its bearing on education. Dr. Hall insists with great earnestness on the necessity of ceasing to mould woman's education on that of man, and of finding an education which shall be adapted to her nature, physical and mental. The volume closes with an account of adolescence in literature, biography, and history.

In the second volume, after a preliminary survey of changes in the senses and in voice, the emotional phenomena of adolescence are treated under the headings of adolescent love and adolescent feeling towards nature. Several chapters deal with social and historical relations; initiations in savage and classical times, confirmation as their correlative in modern religion, the social instincts and institutions of youth, ethnic psychology, and the treatment of uncivilised races, form the subject of successive discussions. In treating the subject of religious conversion, Dr. Hall points out that it is peculiarly a phenomenon of adolescence, and that it has close relations to the sexual life. It is thus," he says, no accidental synchronism of unrelated events that the age of religion and that of sexual maturity coincide." In the chapter on intellectual development and education there is a careful review of education in school and college, and a discussion of its value in the light of the results presented in preceding sections. Dr. Hall does not hesitate to condemn vigorously and comprehensively the studies and methods of schools for their aridity and want of vital relation to the developing individual, and though his criticisms are directed to American schools, they have a wider application.

It will thus be seen that we have in these volumes a text-book of adolescence in which scientific and

That the work took its origin in courses of lectures may perhaps explain in part the diffuseness and repetition which appear in these pages. There is an unnecessarily frequent use of strange words; one is at a loss to understand, for example, what is meant by the 'solipsistic hopo" and by minds that are rily." One meets with long lists of objects and with masses of facts which are not adequately correlated.

66

It is impossible to enter on a discussion of the many theoretical and practical questions which are raised. The treatment of the material, gathered from the most varied sources, is original and suggestive in a high degree; but among the wealth of new material and new conceptions one misses an exact discussion of the method by which the processes of psychogenesis are to be ascertained. Prominent among the data in the book are the results of the questionnaires which have been so much used by Dr. Hall and his pupils. We have, however, no presentation of the difficulties. inherent in such a method of investigation, and of the precautions to be adopted in utilising its results. Apart from this special point there is the difficulty, which does not receive adequate attention, of distinguishing in any stage of adolescent development what is to be regarded as "palæopsychic," what is due to traditions and customs handed down from generation to generation of boys and girls, and lastly, what is conditioned primarily by the awakening mental and physical activity of the individual as he reacts on his experience. There is not sufficient treatment of the idea of individual growth in completeness and complexity, and of its relation to factors of development, the meaning of which is to be sought in past organic history; and one feels that some of the suggestions of racial influences are little more than

interesting fancies. We may illustrate these points by reference to the author's interpretation of the child's attitude towards water. Human infants, we are told in one passage, have an untaught horror of water, and man must learn to swim. This is part of the evidence that there are "psychic vestiges in man which are suggestive of former arboreal life." Again, we learn that "children are phyletically older than women, and after the first shock and fright most of them take the greatest delight in water." This, among other phenomena, may be interpreted as a "pelagic vestige." Do we need arboreal or pelagic vestiges to account for the fact that, while some children dislike water at first and others delight in it, most of them in the end find it an excellent plaything?

W. G. S.

A NATURALIST ON THE EAST COAST. Notes of an East Coast Naturalist. By Arthur H. Patterson. Illustrated in colour by F. Southgate. Pp. xiv +304. (London: Methuen and Co., n.d.) Price 6s.

THE

HE author of these notes, who has been in the habit of spending his spare time in a house-boat moored on Breydon Water and other East Anglian lagoons, has naturally enjoyed opportunities of making observations which are given to few people; for Breydon is a locality probably more famous than any other in the annals of British ornithology as a place where rare birds are in the habit of "dropping in." Moreover, as all field naturalists know, early morning and nightfall, ay, even night itself, are the times when the good things of their lives come to them. Hence the advantage of living on the field. In the latter part of the quarter of a century which these notes cover the author discarded the gun in favour of the field-glass, and could thus give undivided attention to observation without being distracted by the hopes and fears

attendant on the wildfowler's efforts to obtain “a shot."

Breydon is a very carefully protected breeding area. A watcher has been stationed there for several years during the close season; but it will perhaps be disappointing (although we hope it may prove instructive) to ardent advocates of county council "orders" to find that Mr. Patterson writes, "I must, however, state that since stricter preservation has obtained, not nearly so many birds are to be seen on Breydon." It is impossible to deny the fact that no amount of preservation will bring back the breeding birds which left us with the spread of population and buildings, and the alterations in the system of agriculture. The spoonbills come and go in safety, but the late date at which they arrive shows that nesting is not the object of their visits. As a former east coast naturalist, remarkable for his common-sense views of such subjects, 'wrote years ago, "Unless England becomes dispeopled and uncultivated, nothing can ever bring back in numbers or variety the wealth of the ancient avifauna." But for all that the naturalist still" has his delights" on Breydon; as, for instance, on May 15, 1893, when the author, paddling up stream, saw on the lumps" still uncovered by water "a congrega

tion of no less than eighteen Black Terns, more than fifty Turnstones, several Common and Arctic Terns, a number of Dunlins, Grey Plovers, Whimbrel and Godwits, and not least worthy of a glance, three Spoonbills." To one who is learned in the fishes of Our seas, ready access to Yarmouth Market, and an extensive acquaintance among the fishermen have been a great advantage, and many a rare fish has the author rescued from oblivion and added to the east coast catalogue of fishes. Not the least valuable part of the book is that containing the fish notes, although the bulk of the volume deals with birds, their migrations and habits. Among the various interesting scraps of information here collected we find a record of the value of birds and the prices realised by the wildfowler and at the sales of noted collections; accounts of wildfowl brought into the | market in hard winters, and incidents related by oldtime wildfowlers, whose habits and customs, as well as their recollections of the hard winters and wildfowl of the "old days," are most amusing. Whales, crabs, lobsters, toads, insects, and rats all find a place in these very readable notes. Indeed, some of the most valuable paragraphs relate to the old English black rat, now extinct in most parts of the country, but so abundant in the malthouses and sail lofts of Yarmouth that Mr. Patterson can write of "a plague of Black Rats." This and many other of the records are well worth preserving as of permanent value, and the author is quite justified in thinking that some value may attach to these notes and observations "owing to their dealing with a period during which great changes have taken place in the habitat of the local

fauna."

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Tables for Qualitative Chemical Analysis. By Prof. A. Liversidge, M.A., LL.D., F.R.S. (London: Macmillan and Co., Ltd., 1904.) Price 4s. 6d. net. THE HE introductory chapter of Prof. Liversidge's book makes it clear that it is only when analytical methods are used intelligently that the time devoted to qualitative analysis is well spent, and to that end the student must have some preliminary training in other kinds of simple practical work (not described in the book), and be frequently supervised, lectured to, and examined as his work progresses.

All this is very right and proper, and quite as it should be, but leaving out the excellent counsel of perfection set forth in the introduction, the book is very much like other books on this subject. That is to say, it describes a series of qualitative tests in which inorganic and organic bases and acids, rare metals, and alkaloids are treated individually, and then collectively in tables after the old-established manner and with the old-established purpose.

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Prof. Liversidge attaches great importance to the study of qualitative analysis as a means as well as an end of chemical education. It is an opinion very widely held, and is well worth discussing. The fact is sometimes lost sight of that chemistry is a handicraft as well as a science, and that its science is as yet not exact.

Perhaps there is no branch of chemistry wherein the skill of the craftsman is in greater demand, or the inexactness of the science more clearly emphasised, than in chemical analysis.

A student may study intelligently the reactions for individual elements, and so learn their properties; but he finds that when they are mixed they behave differently, and the more observant and careful he is the more will these subtle influences, which conform to no equation, become apparent.

66

OUR BOOK SHELF.
naturelles. By Félix Le Dantec. Pp.
(Paris: Félix Alcan, 1904.) Price

Les Lois
xvi + 308.
6 francs.
JUST as
anyone can play the piano" with a piano-
player, so anyone can write a book on the philosophy
of science. The result gives satisfaction and pleasure
other, but whether his particular interpretation is
to the performer in one case and to the writer in the
equally satisfying to an outsider is another question.
The effects are, however, more lasting in the case
of the author, for we are getting such an enormous
accumulation of books on space, matter, force, the
ether, and laws of nature that it is becoming a
Wonder who finds time to read them or even to cut
their pages, if the publisher has failed to attend to his
proper duties in this respect.

Let us examine how M. Le Dantec deals with thermodynamical considerations. In commencing he supposes bodies to have definite thermic masses, and he defines quantities of heat by the products of these masses into the changes of temperature. He according to which the heat gained by one body is also enunciates the principle of conservation of heat equal to that lost by another. But in the first place the quantities which he calls thermic masses are not constant for the same body between the same limits of temperature, but they also depend on whether the changes take place at constant pressure or constant volume; and, in the second place, his equation of con

No substance is insoluble; mass action is a power-servation of heat is contrary to common experience ful factor; a precipitate will carry down a substance which should, for all he knows, remain in solution, and a substance will retain another in solution which, for equally occult reasons, should form a precipitate.

Tables for the analysis of mixtures, which are based on the behaviour of single substances by a process of simple logic, become artificial and illusory, and give a sense of false security which subsequent experience alone can dispel.

of what happens when two rough bodies rub against
each other. In the next chapter the author goes on
a different tack, and speaks of the equivalence of
quantities of work and quantities of heat, quite
regardless (to all outside appearances) of the fact
that the term "quantity of heat" is meaningless
except in the case of passage of heat from one body
to another. In the next chapter the author condemns
the use of the term "quantity of heat" altogether.
What ideas can a reader form of the nature of
physical laws after perusing such a series of chapters
as this?

Nature Teaching. By F. Watts and W. G. Freeman.
Pp. xi+ 193.
Price
(London: Murray, 1904.)
3s. 6d.

THIS little book forms a welcome change from the
many appearing under similar titles in that it is
avowedly based upon experiments, and treats of
not merely read up. Dealing in the main with the life
of the plant, it describes a simple series of experiments
within the capacity of an elementary school or an even-
ing continuation class, illustrating the function of seed,
root, stem, leaf, &c., and amplifying the knowledge
thus obtained with further examples drawn from the
practice of the garden or the farm. A certain lack of
definiteness in the description of experiments militates
at times against the spirit in which the book has been
conceived; in a subject where everything depends upon
the cultivation of accurate observation and rigorous
scientific method the authors should not allow them-
selves to fall into the slipshod generalised accounts of
things which are the bane of so much of the current

Is this a subject for extended study on the part of a beginner in chemistry? In the opinion of the writer the preparation of simple substances and a careful study of their properties, into which the general principles of qualitative and quantitative analysis are introduced, is his proper sphere of work. The host of reactions and elaborate tables of separa-things about which the writers really know and have tions, and still more the countless precautions, Kunstgriffe, and manipulative details of practical analysis are a part of the handicraft of the specialist in chemistry. To thrust this work upon a beginner who is not to be a specialist is almost equivalent to expecting a student of mechanics, who is not to be an engineer, to work a lathe use a planing machine. The crux of the whole question lies in this, that qualitative analysis is a branch of practical work, calling itself chemistry, which can be easily adapted to the process of examination. Were the practical examination banished from the syllabus and replaced by note-teaching of this nature. For instance, in their account books supervised, signed and submitted by the responsible demonstrator or teacher of recognised standing, the mass of ill-digested analytical tests and tables would soon vanish from the curricula of schools and colleges, and its place supplied by a series of rational exercises. J. B. C.

or

of striking cuttings, the authors do not direct attention to the differences in the management of herbaceous and woody cuttings, the time of year at which they should be struck, and so forth, so that the teacher without experience would be apt to fumble over the matter at first, and would in real life be discouraged from trying any experiments in this particular direction unless

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