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NOW READY, the JAVUJRY ISSUE of

SCHOOL:

A Monthly Record of Educational Thought and Progress.

Edited by R. B. LATTIMER.
Demy 4to. January. Price 6d. net.

CONTENTS:
PRACTICE AND PRECEPT :

An Acknowledgment—The Headmasters' Conference-The Teaching
of Geography, The London Scholarship Scheme-Obsolete Weights
and Measures-Army Commissions for University Candidates-What

Our Educational System Needs.
THE PROPER FUNCTION OF EXAMINATIONS. By a Member of

Four Examining Boards.
SOME NOTES ON THE TEACHING OF HISTORY. By R. F.

CHOLMELEY, M.A.
WHERE ARE THE REAPERS ?
COMMON ROOM PAPERS. The Greek Question.
EDUCATION DAY BY DAY.
OUR LEADERS.-XIII. Edward Thring.
THE TEACHERS' FORUM. State Leaving Examinations.
SCOTCH EDUCATION.-1. Elementary. By John CLARKE, M.A.
THE BOOK AND ITS WRITER. Six Great Schoolmasters. By

THEODORE WALKOND, M A.
WOMEN AS TEACHERS. By Miss HOSKYNS ABRAHALL.
GERMAN LETTER. Local Inspection of German Schools. By

Dr. OTTU W. BEYER.
HORTICULTURAL TRAINING OF WOMEN. By J. C. Medd.
HOW THE ACT WORKS. Leicestershire.
REVIEWS:

An Unwritten Chapter in the History of Education – Murray's

Cla-sical Atlas. MINOR NOTICES. BOOKS RECEIVED.

JOHN MURRAY, ALBEMARLE STREET, W.

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THURSDAY, JANUARY 5 1905.

nach Abbe," published in 1893. Being unable to undertake the work himself, the idea suggested itself

that a better purpose would be served by obtaining MODERN OPTICAL METHODS.

the collaboration of a number of joint authors, and

that no better body of men could be found for the Die Bilderzeugung in optischen Instrumenten, vom

purpose than the scientific staff of the Zeiss firm. Standpunkte der geometrischen Optik.

By the

The work has been divided among the seven joint Scientific Staff of Carl Zeiss's Works. Edited by

authors as follow's :— The first chapter, dealing with M. von Röhr. Pp. 588; with 133 woodcuts. (Berlin :

the fundamental principles of optics, including the laws Julius Springer, 1904.)

of re'raction, the principle of minimum path, and the Grundzüge der Theorie der optischen Instrumente characteristic function, is contributed by Drs. Czapski nach Abbe. By Dr. Siegfried Czapski. Second

and Siedentopf; Drs. König and von Röhr contribute edition. Edited by Dr. O. Eppenstein, with the assistance of M. von Röhr. Pp. 490; with 176 fifth, on spherical aberration, in which latter is con

the second chapter, on formulæ of calculation, and the woodcuts. (Leipzig : Johann Ambrosius Barth,

tained a complete exposition of Abbe's method of in1904.)

variants and its application to the determination of the THE CHE old geometrical optics which we used to read

ten corrections determined by the problem of Seidel. at Cambridge was a delightful subject. It The chapters on chromatic aberration and on deterwould have been a still more delightful subject had

mination of optic systems according to the theory of examiners set better questions on it. Probably no aberrations (chapters vi., vii.) are contributed by Dr. other branch of mathematics would lend itself so well

König alone. “ The Geometrical Theory of Images to the kind of treatment which is now fortunately after E. Abbe " is the title of the third chapter, by Dr. coming into fashion, viz. the use of graphical and ex

Mandersleb. In the fourth chapter, by Dr. P. Culperimental methods. If the German system of Lehr

mann, on the realisation of optical images, we actually freiheit prevailed in this country I would rather teach

do find our old friend the formula geometrical optics to elementary class than

I geometry adapted to modern requirements.

This elementary optics, however, bears about the same relation to the optics treated in the first of these in a position, however, of subsidiary importance. Dr. books that Newton's deductions from Kepler's laws Löwe contributes a chapter on prisms, while Dr. von bear to the planetary theory. The analogy is the more Röhr is responsible for the last two chapters, dealing complete in that both the optician and the astronomer with the breadths of pencils, penetration, brightness have found it impossible to obtain an exact solution by of images, and similar matters. direct methods, and they have therefore been led to em- The second of these books is of a more elementary ploy the method of trial and error in order to obtain and practical character. It contains a general dissuccessive approximations giving the desired results cussion of images formed by small pencils, and illusto closer and closer degrees of accuracy. As Messrs. trated descriptions of the principal optical instruments. Czapsky and Siedentopf point out (p. 25), the exact The corrections are discussed, but the discussions are determination of the forms of the refracting surfaces less mathematical. The theory of conjugate foci rerequired to produce exact images subject to given ceives fairly full treatment, and among the interesting conditions has never been effected, except in a few features which we notice at a first glance, attention cases, such as the Cartesian oval, in which rays from may be directed to the series of sections of a pencil of one focus converge to a point in the other. We light on p. 24, and the figures of an object and its therefore take spherical surfaces, and by calculating image on p. 40, where the object is an arrow in a the various kinds of aberration, show how they may plane through the axis of a lens, and is bisected by be corrected. It is, however, interesting to learn that the focal plane of the lens. the theory of non-spherical surfaces has quite recently This is the second edition of a book of which the been put into practice in the Zeiss works for the first first edition was written for Winkelmann's time in the construction of lenses other than large buch der Physik." Of matter new in this edition, Dr. reflectors and refractors for telescopes. It has, in fact, Eppenstein contributes chapters on screens, on probeen found possible to correct certain residual jection apparatus, and on the illumination of objects; aberrations by applying finishing touches to the lenses chapters on vision, on photographic objectives, and on giving them a slight deviation from sphericity.

spectacles are contributed by Dr. M. von Röhr. The analogy between the problems of the optician The perfection to which the manufacture of optical and the astronomer is made still closer by observing instruments has been brought by the Zeiss firm is well how different specialists have confined their attention known, and it is also pretty generally realised that to particular kinds of aberration in the one case and the results attained could not have been accomplished of perturbation in the other, and have devised special by an establishment run on purely business lines by methods for simplifying the calculation of the corre- 'practical men " falsely so-called. The usual stock sponding terms.

form in which the last named class of individual rein his preface Dr. Czapski tells us that the present commends his wares to the public is the stereotyped work owed its origin to the demand for a revised statement that “ The materials used in the preparation edition of his Theorie der optischen Instrumente of these goods are of the best quality obtainable.” NO. 1836, VOL. 71]

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The present books furnish abundant proof that this sporadically through botanical literature into the statement is particularly applicable to the Zeiss instru- compass of a short, well written book. The work is ments in regard to the quality of those materials most illustrated by blocks in the text, which show in a essential for the production of good optical apparatus, satisfactory manner the points to be brought out. viz. brains and knowledge of advanced mathematics. Miss Ferguson's memoir has a more limited scope,

G. H. BRYAN. but this allows her to devote more space to her own

researches, which have been very extensive in the AMERICAN CYTOLOGY.

cytology of the spore-production of conifers. It is

quite remarkable to see how two cytologists, writing Fecundation in Plants. By David M. Mottier, Ph.D.

almost simultaneously, can hold so divergent views on Pp. viii + 187. (Washington : Published by the

fundamental subjects. While Mottier sees in Carnegie Institution, 1904.)

fusion of sexual nuclei the blending of two lines of Contributions to the Knowledge of the Life-History of descent, Miss Ferguson's researches lead her to believe Pinus, with Special Reference to Sporogenesis, the

that no fusion-nucleus, combining the paternal and Development of the Gametophytes and Fertilisation.

maternal hereditary substances, is formed. Rather By Margaret C. Ferguson, Ph. D.

.
Pp. 153

the processes of mitosis allow these to be kept apart (Washington : Published by the

Washington during the life of the offspring, and the " reduction" Academy of Sciences, 1904.)

or qualitative division occurring some time during the

MR. MOTTIER'S Fecundation in Plants" gives life-cycle secures that the gametes shalobera duten

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those who are interested cytology an It is writer is concerned with account of the phenomena of fertilisation throughout the relation of mitosis to Mendel's views rather than the vegetable kingdom, written by one who has carried to Weismann's hypothesis. With regard to synapsis, on investigations in several branches of the subject with Miss Ferguson believes it to be a normal stage in success. His practical acquaintance with his subject heterotypic mitosis. Another point of difference is the confers even on his descriptions of the investigations mode of origin of the double chromosomes of heteroof others a freshness which makes his work a pleasure typic mitosis. Miss Ferguson finds confirmation in to read. The first chapter is perhaps the most generally her preparations for the view (first published by the interesting. In it he gives an account of some of the writer of this review in 1896, Proc. Roy. Irish Acad.) vexed problems of karyology which are at present that the two arms of the chromosomes are approxicalling out so much controversy among cytologists. mated pieces of the nuclear thread, and do not arise by Among these problems may be mentioned the existence longitudinal cleavage as Mottier believes. This interof centrosomes, the homology of centrosomes and pretation seems to be gaining ground, and the Louvain blepharoplasts, the nature of synapsis, the significance school, once much opposed to it, has recently of the sexual process, and the numerical reduction of accepted it, putting the folding back, however, to the chromosomes. The author's method of discussion is synaptic stage. The reviewer's investigations seem to candid. He avoids being dogmatic in expressing his suggest the possibility that two distinct foldings take own views, although he criticises somewhat severely place, one during synapsis and another between that the observations of others. He holds that centrosomes stage and the differentiation of the chromosomes. and centrospheres do not occur in plants higher than Whatever views are held on these disputed matters, the liverworts, and are, indeed, only well established all cytologists are indebted to the author for her in a few of the Thallophyta. It is remarkable that beautiful drawings, which are reproduced in a series he does not allude to the possibility that the radiations of twenty-four plates. at the poles of mitoses may be in part artefacts pro- There is no doubt that the publication of these tuu duced by the fixing agents. He considers Belajeff memoirs, the one by the Carnegie Institution and the hasty in coming to the conclusion that the centrosome other by the Washington Academy, will be of much is the homologue of the blepharoplast; but he admits service to those engaged in cytological research. later on that certain “ facts lend encouragement to

H. H. D. the belief that centrosome and blepharoplast may be homologous structures." Mottier regards synapsis

PHYSICAL RESEARCH AT LEYDEN. as due in a large measure to the action of reagents. He accepts Strasburger's theory of the numerical Het Natuurkundig Laboratorium der Ryks-linicersi. reduction of chromosomes as a good working hypo- teit te Leiden in de Jaren 1882-1904. Gedenkboek thesis, and he holds now that there is no evidence for aangeboden aan den Hoogleeraar H. Kamerlingh Weismann's “ reduction to be found in the mitoses Onnes, Directeur van het Laboratorium, by gelegenof plants. His candid expression of doubt as to the heid van zyn 25-jarig Doctoraat op 10 Juli 1904. persistent individuality of the chromosomes preserved Pp. viii + 288. (Leyden : Eduard Ydo, 1904.)

, a miraculous

of Unitypical of his attitude of independence.

versity, and presented to him on the twenty-fifth The succeeding chapters give an account of fertil. anniversary of his receiving the degree of Ph.D. It isation in types taken from the various subdivisions differs in character from the usual collections of of the vegetable kingdom. These descriptions are scientific papers which it has become the fashion on most useful in bringing together what is scattered the Continent to present to eminent men of science on

through the successive mitosesso often assumed; THIS volume was prepared by colleagues and pupils

similar occasions. Since 1882 Prof. Onnes has been of researches on Hall's phenomenon in bismuth at director of the physical laboratory at the University various temperatures down to the boiling point of of Leyden, and the book gives a description of the oxygen, measurements of the dielectric constant of growth of the institution since his accession to the liquid oxygen and liquid nitrous oxide, and of the directorship, of its present condition, and of the work absorption of Hertz vibrations by salt solutions. carried out by himself and by his pupils under his A detailed account of all the research work is pubsupervision. In a sense it is a matter for regret that lished regularly in the Communications from the by the nature of the case he himself had to be excluded physical laboratory at Leyden, the issue of which was from the list of contributors; on several of the subjects commenced in 1892, but the present papers give a dealt with it would be interesting to have the director's useful general summary of the work carried out, prepersonal view's.

sented in a manner which should make it intelligible After an eloquent dedication from the hand of Prof. to the uninitiated. Bosscha, we find in the first chapter, compiled by Prof. The volume bears ample testimony to the success Haga and others, a detailed description of the labor- which has attended Prof. Onnes's manifold labours for atory and of the more important machinery and his laboratory, which owes to him its position as one fittings, particularly those belonging to the

cryo- of the best known institutions of its kind. It is well genic" department, to which Prof. Onnes has devoted illustrated, and contains as a frontispiece a striking most of his personal labours; the low temperature likeness of Prof. Onnes, apparently after a drawing. baths prepared here are extensively used throughout the laboratory for various researches. In an appendix to this chapter Dr. Siertsema gives

PRICTICAL SILICATE ANALYSIS. an interesting account of the training school for Manual of the Chemical Analysis of Rocks. By H. S. apprentice mechanics instituted by Prof. Onnes in Washington, Ph.D. Pp. ix + 183. (New York : connection with the laboratory. This institution is Wiley and Sons; London : Chapman and Hall, Ltd., probably unique; it was started in 1886 with one pupil, 1904.) Price 8s. 6d, net. and the number has risen steadily until this session no less than thirty-three boys are receiving systematic

F late years greatly increased attention has been OF

directed to the chemical investigation of rocks, instruction in the various mechanical arts, with and the science of petrology has been enriched by many the object of qualifying themselves as instrument excellent analyses. Among these the work of the makers, glass-blowers, electricians, and for similar pro- | United States Geological Survey deservedly holds the fessions. The boys are supposed to assist to a certain highest place, both on account of its abundance and extent in the routine work of the laboratory and earn its thoroughness. The present treatise arises from an corresponding small wages, while in the evening they endeavour to make the methods used by Clarke, have to attend classes in the municipal technical | Hillebrand, and other chemists in the United States institute. A better training for the purpose could | laboratory available to all workers. It is excellently hardly be imagined, and one is not astonished to learn clear and detailed, and though the experienced analyst that after the completion of the three years' course will not find in it much that is not already published the boys appear to be much in request in laboratories in more succinct form in the official Bulletins of the and various engineering and technical works.

Survey, he will glean a few details of manipulation In chapter ii. thermodynamical investigations are and discussions of the bearings of chemical petrology reviewed; Prof. van der Waals gives an account of that will at any rate repay perusal. Prof. Onnes's researches on thermodynamical surfaces, The author intends his book to be used mainly by Prof. Kuenen writes on the phenomena of condensa- the rather numerous class of geologists and petrotion of binary mixtures, and there are further articles logists who combine a fair knowledge of chemistry on accurate isothermals of gases, on the construction with a desire to make their own rock analyses. Unof models of surfaces, and on capillarity and viscosity doubtedly this is a far more satisfactory proceeding of liquids up to the critical region.

than, as is usually done, to have the analyses executed The third chapter, edited by Prof. Lorentz and by some analyst who has no special knowledge of the others, is devoted to optical and magneto-optical intricacies of this part of practical chemistry, and work; here we find a discussion of experiments on the follows methods which are discredited or discarded. reflection of light by mirrors, on the magnetic rota- In any case such a worker will do well to place himtion of the plane of polarisation in gases, liquefied self, for a time at least, under some teacher who is gases and other liquids, on the influence of pressure thoroughly at home in the subject; we hope that this on the rotation of sugar solutions, on the reflection of book will not stimulate the production of analyses of light by magnetised mirrors (Kerr's phenomenon), and rocks by students in course of training. Much of the an account of Zeeman's discovery of the modification worst analytical work with which chemical petrology in spectra by magnetic forces. The phenomenon dis- is burdened has been executed in that way. If it helps covered by Egoroff and Georgiewsky, that a sodium to spread the knowledge of the methods used by Clarke flame placed in

a magnetic field emits partially and Hillebrand this book will do much good, as it is polarised light, was investigated by Prof. Lorentz desirable that these should henceforward be recognised himself, and appears to be closely connected with as standards, from which any important departure Zeeman's phenomenon.

should be notified when the results are published. In the last chapter Prof. Zeeman gives a description In a few respects Dr. Washington has simplified the

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standard American procedure. We think this is wise, The whole trend of modern organic synthesis seems and, while we endorse his opinion that only the best to lie in this direction. Thus the caustic alkalis have work should be aimed at, we do not think that this been replaced in many cases by alcoholic solutions of means that the very elaborate American analyses

sodium ethoxide, by diethylamine, pyridine, or chalk, should be emulated by the ordinary worker. From

the strong mineral acids by phosphoric, boric, or one

of the organic acids. High temperatures have given twenty to twenty-five elements are usually sought for place to lower ones. The days of so-called "pyroby the American chemists, and nearly one-half of these genic synthesis " are past. No one nowadays makes may be present in less than i per cent of the total organic compounds by the aid of a red-hot tube. rock. Such analyses look exceedingly well on paper,

In this connection it is suggestive that the fundabut require the greatest experience and manipulative mental reactions of living matter which embrace dexterity if they are to be trustworthy.

oxidation and reduction of a far-reaching kind, as well Moreover,

as synthetic processes more complex than anything their value is as yet not beyond question. Certainly | achieved in the laboratory, are all effected at ordinary an analysis in which ten or twelve elements are deter- temperatures and with the mildest reagents. mined as exactly as possible is more welcome than an It follows, therefore, that the more closely organic analysis which is more elaborate but less accurate. chemists succeed in imitating these conditions the We notice that the author discourages the routine

more surely will those mysterious contact or fermentexecution of duplicates. No doubt this is right; they plasm, but not unknown in the laboratory, approach

ation problems usually associated with living prototake up much time, and may be useless or misleading ; solution.

J. B. C. it is better for the experienced chemist to occupy himself in the most thorough testing of his re

A Further Course of Practical Science. By J. H.

Leonard and W. H. Salmon. Pp. ix + 224. agents, the purity of which is never above suspicion.

(London: John Murray, 1904.) Price 25. Still, there can be no doubt that duplicate analyses

In this book the principles of natural science are do show how far it is possible for the results to vary

taught and enforced in a scientific manner by means when two samples of the same powder are analysed.

of a course of experimental work, simple in character, They help to check any exaggerated confidence in but involving quantitative measurements, and carried analytical refinements. In this respect it would be out personally by the student. To begin with, lengths interesting to know what are the probable limits of are measured with an ordinary rule, and tests are error in analyses executed by the methods given in this made in order to find out the limits of accuracy within

which the measurements may be relied on. These book. The author gives his opinion (apparently not

measurements serve as an introduction to " physical founded on any special investigations), and it strikes arithmetic," simple arithmetical computations us that he is more sanguine in this respect than the specially suitable for dealing with numbers which are majority of experienced silicate analysts in Britain or avowedly only approximately correct. Then follows a on the Continent.

chapter on elementary mensuration involving the estimation of angles, lengths, areas, and volumes, the

balance very wisely sharing in this work. OUR BOOK SHELF.

Experiments are devised to illustrate some of

the fundamental properties of matter, such as those Application of some General Reactions to Investi

of indestructibility, inertia, porosity, ductility, &c. gations in Organic Chemistry. By Dr. Lassar

The next six chapters deal with mechanics, the subCohn. Translated by J. B. Tingle, B.A. Pp. 101. jects including uniform linear acceleration, Newton's (New York: Wiley and Sons; London : Chapman laws, relative motion, statical equilibrium of uniplanar

: and Hall, Ltd., 1904.) Price 4s. 6d. net.

forces, and simple machines. This difficult section is It would be difficult to say with what object and for not treated in a very satisfactory manner. The what class of readers this little volume (it is scarcely method is too deductive, the experiments are some more than a pamphlet, and may be read in an hour) what scanty and not very well chosen. Thus there was written. Yet anyone engaged in the practical pur- is no direct verification of the fundamental principle suit of organic chemistry cannot fail to be interested of the conservation of momentum, Vectors, though in it. One may say roughly that the book treats of introduced, are not made sufficiently prominent, and the unsystematic part of organic chemistry, i.e. of the in the so-called "simple machines " it seems rather ordinary reactions which do not succeed, and how they antiquated to find the three kinds of levers, the three may be made to do so.

systems of pulleys, the wedge, &c., introduced. Without always offering a very satisfactory explan- In the concluding chapters relating to the properties ation of the causes of success or failure, for the terms of liquids and gases, and the nature of heat, the “protective influence" and “contact action" are authors are happier in their treatment, notwithstandafter all merely names, the author points out how an ing an occasional looseness in the statement of a apparently unimportant modification may affect the principle. The book deserves to be very favourably whole course of a reaction and convert an unprofitable received, and teachers will find that arrangements method into a successful or commercially lucrative have been made to facilitate the purchase of the one. Incidentally, he urges the systematic study of apparatus necessary for conducting the experiments. these anomalous reactions.

As an example may be mentioned the well known Die drahtlose Telegraphie. By Dr. Gustav Eichhorn. fact that the accidental introduction of a few drops of Pp. x+ 256; numerous figures. (Leipzig : Veit and mercury into the experimental vessel, in which the Co.) Price 5 marks. preparation of phthalic acid from naphthalene was in This is an elementary exposition of the principles and progress, rendered the operation and consequently the practice of wireless telegraphy with especial reference production of artificial indigo a success.

to the systems developed by Dr. Braun. It is evidently As a rule the difficulties encountered by the intended to enable practical to become anomalous behaviour of organic compounds are met acquainted with this method without, at the same not by more drastic treatment, but by milder reagents. time, any attempt being made to give such a complete

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