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likely that the greater number of earthquakes felt in result that a blow at an epicentre may at a distance the world belong to this latter class. All of them from the same be recorded as a long train of waves. represent a relief of stress, and the discussion on the When Major Dutton suggests to his readers that sources of earth stresses, commencing with the con- the Seismological Investigation Committee of the tractional hypothesis and concluding with the results British Association carries on its work in consequence of investigations by Prof. George Darwin, are attrac- of financial aid received from the British Government, tive not only to seismologists but to all who wish to we recognise that he shares a widespread mislearn something about the inside of the world on which apprehension. they live.

Much is said relating to the elasticity of rocks, in Some fifty pages are given up to descriptions of connection with which an elaborate table, the result of seismoscopes and seismographs, attention being par- investigations made by Prof. Nagaoka, of Tokio, is ticularly directed to those which record unfelt tele- reproduced. A second long table is that drawn up by seismic movements. We cannot say that the concepts M. Montessus de Ballore relating to the distribution relating to seismic wave motion put forward are of seismicity. generally accepted, but such as they are we may say The illustrations, of which there are sixty-three, are that they represent modern views. About the ampli- for the most part excellent, but there are one or two tudes and periods of earthquake waves seismologists photomechanical reproductions of instruments which have certain definite information, but about the magni- we imagine will give more delight to their authors at tudes of these elements, particularly for waves which the sight of their own shaky caligraphy than to the have travelled over long paths, much has yet to be ordinary reader. learned. For this latter class of movement it is pointed Taken as a whole, the work is one to be read by all out that discordant results are found in tables showing who wish to know what is known respecting the prothe speeds at which they were propagated. The author pagation of wave motion in our earth since the ininclines to the view that the differences which have vention of the seismograph, and it is destined to receive been noted are due to variability in the delicacy of a hearty welcome. instruments employed to pick up a wave or group. In great measure this may be true, but it

TECHNICAL MECHANICS. seems to us that marked errors may also arise in con- Die technische Mechanik : elementares Lehrbuch fur sequence of inaccuracy in determining the time at mittlere maschienentechnische Fachschulen und which waves were generated at their origin.

Hilfsbuch für studierende höherer technischer Then, again, there are those who incline to a belief,

Lehranstalten. By P. Stephan, &c. Erster Teil : which they sustain with arguments deserving close

Mechanik Starrer Körper. Pp. viii + 344. (Leipzig : consideration, that within our earth convection currents Teubner, 1904.) Price 7 marks. exist; it would follow from this that along similar

IN N the very early part of this excellent work there paths, or even along the same path, earthquake speeds is a certain lack of system, inasmuch as, although should vary.

the author very properly treats first of the equilibrium Notwithstanding these uncertainties, the author of a particle, he assumes the nature of the stress holds the opinion that remarkable and unexpected exerted in such rigid bodies as the bars of a frameresults which fit well within errors of observation have work, the crank and connecting rod of an engine, &c. been reached.

The nature of such forces is never properly appreciated Two serious difficulties, for the explanation of which by the student who is truly a beginner in the subject we are asked to wait patiently, relate to the lengthen- of dynamics—and, indeed, there is no part of statics ing of wave periods and the total duration of a dis- in which students of even very considerable experience turbance as it radiates. We will suggest that the are so apt to go wrong as that relating to the forces former phenomenon may perhaps be at least partially exerted by jointed bars. The author treats from the explained by assuming that in the vicinity of an origin outset the equilibrium of forces acting in space of three the records refer to forced vibrations, while at a dimensions without having previously disposed of the distance the motion represents a periodic natural move- simpler two dimensional case, a course which meets ment of the crust which varies with its heterogeneity. with the approval of many teachers, although it seems With regard to the second difficulty, now and then we to the reviewer to be the less simple method. Herr have evidences that a disturbance recorded at a station Stephan enunciates the parallelogram law for the comfar removed from an origin may be reinforced and position of forces (or vectors generally) at the outset, lengthened by a repetition of the first disturbance and assumes it as a result of experiment—which, on which has reached the station by travelling in an the whole, is perhaps the wisest plan for a teacher. opposite direction round the world. Generally, how- Near the end of the book, however, he gives the ever, the record from a horizontal pendulum near to ordinary Newtonian proof of the proposition. an origin appears to move as long as, if not longer He gives very early and very clearly the method than, a similar instrument at a distant station, which of determining the resultant of a system of coplanar means that in certain instances the author's difficulty forces acting on a body (other than a particle) by means is non-existent. Finally, it must be borne in mind of the force and funicular polygons-a subject in that a single impulse at an origin results in the birth which English students are, as a rule, extremely weak. of a series of waves which reach a distant station along There is a section on the determination of the centres different paths and with different speeds, with the of gravity of all the bodies usually figured in our English books, followed by a discussion of all the moments of inertia for all plane areas bounded by ordinary simple machines—with this difference, that right lines. In the absence of this simple rule, a ponHerr Stephan's figures are much better than those of derous application of the integral calculus is the only our text-books. Then follows a discussion of friction, refuge of the student. A somewhat similar "particle in which, although the author almost invariably solves rule saves reams of ponderous calculus work in his problems by introducing the normal force N and hydrostatics; but these rules are not widely known. the friction “N, he does not omit to point out the Herr. Stephan very properly makes short work of utility of the total resistance and the angle of friction. D'Alembert's principle, deducing it directly from He underestimates this utility, however, in solving a Newton's axioms ii. and iii., so that, although he simple problem by the N and 'N method, and in his employs the term centrifugal force," he is careful, final results (p. 118) substituting the angle of friction except in one instance, to show that it is a force exerted -a process which simply obscures the merit of the by, and not on, a moving particle. The exceptional second (and much shorter) method—with the remark | instance occurs at p. 281, where he is calculating the that the example shows the advantage which the intro- tension in a driving belt which passes over the surfaces duction of the angle of friction" occasionally offers." of two revolving cylinders. Here he speaks of a small The truth is that in the hands of a skilful student the element of the band as experiencing” a centrifugal geometrical method founded on the employment of the force, which is duly represented, in the usual way, by angle of friction and the total resistance is almost a centre-flying arrow. His subsequent teaching, howalways more neat, direct, and simple than the ever, removes the erroneous notion herein contained. analytical, or N and “N, method. It can be conceded, The book is wonderfully well printed and illustrated, however, that for engineering students, and technical as well as free from mistakes. On p. 15 " Punkte" students generally, this analytical method is the safer, should clearly be “ Kräfte," and on p. 187 the reference although the longer, and requires less of the esprit should be to Fig. 131 and not to Fig. 135. The theory mathématique. The nature of rolling resistance, is illustrated by nearly 200 examples. which seldom finds mention in our English books, is To all students who desire to attain a real and well explained and illustrated by several applications physical conception of the subject Herr Stephan's work (pp. 147, &c.). Indeed, the whole of Herr Stephan's can be very strongly recommended. treatment of the machines (screw presses, cranes,

GEORGE M. MINCHIN. friction band-brakes, &c.) commonly discussed is excellent, and occupies a very large part of the treatise; it is, in fact, the best and most useful portion of the book.

OUR BOOK SHELF. The only kind of catenary treated of in this volume Machine Drawing. By Alfred P. Hill. Pp. 83. is the parabola of suspension bridges, to which only (London : P. S. King and Son, 1904.) Price 25. 6. two pages and two illustrative examples are devoted. net. Doubtless the subject will receive more consideration In this text-book the author presents a course of inin some subsequent volume.

struction which he considers suitable for students Herr Stephan is very careful to avoid errors in his , attending elementary drawing classes who are unable figures, and to represent the lines of action of three

to spare more than one evening per week, and whose forces when they keep a body in equilibrium as meet-machine drawing. Three dozen plates are given,

technical training is thus confined to the one subject of ing in a point-a very elementary condition not always affording a choice of examples to be copied to scale observed in our text-books. Once, however, he over- from the dimensions figured, some of which are prolooks this necessity, and represents the lines of action portional dimensions covering a range of sizes. Accomof three forces acting on a bar in a framework (Fig.

panying the plates are descriptive accounts of the 164) as forming a triangle of very respectable area.

construction and uses of the machine parts drawn, In the section dealing with the equilibrium of frame- where space is available, formula and physical data

with sets of questions founded thereon. At intervals, works of jointed bars, he directs attention to the obvious are introduced and used in making calculations illusfact, which is not usually mentioned in our books, that trating machine design. This crude attempt to teach even if the bars are loaded throughout their lengths applied mechanics along with elementary machine (by their own weights or otherwise) the stresses can

drawing seems to a mistake, as, in the be calculated by taking any of the bars as unloaded

absence of a knowledge of mechanical principles, such

formulæ as are given become mere rules of thumb, and and weightless, and then superposing the calculated any attempt to apply them independently cannot fail results (p. 197). This simple principle he applies in a to be disastrous, as, for instance, in the author's special case, and it is one which on many occasions method of estimating the limiting speed of a fly-wheel might be employed with great advantage.

on p. 42. The time wasted on these premature calThe last hundred pages are devoted to kinetics of an

culations might very profitably be spent with rule, elementary kind—including the theory of direct careful and complete dimensioned sketches of actual

callipers, and squared paper, in measuring and making collision of spheres, the compound pendulum, &c.- machine parts, and so cultivating the habit of closely together with a section on the moments of inertia of and accurately observing constructional details. various figures and solids. There is no mention made Errors abound throughout the book. The author is of the very simple and useful rule that a triangular

not a safe guide even in such a small detail as the area can be replaced by three equal particles placed at projection of a hexagonal nut, while his statement on

p. 44 that “heat and work are mutually controthe middle points of its sides—a rule which saves an vertible " is a fair index of the scientific value of the enormous amount of trouble in the calculation of work. The volume is somewhat redeemed by a few

us

good plates prepared from working drawings supplied

LETTERS TO THE EDITOR. by makers, but in many cases the figures indicating [The Editor does not hold himself responsible for opinions dimensions are, unfortunately, so small as scarcely to be legible.

expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of rejected

manuscripts intended for this or any other part of NATURE. An Elementary Class-book of Practical Coal-mining. No notice is taken of anonymous communications.]

By T. H. Cockin. Pp. xii +428. (London : Crosby
Lockwood and Son, 1904.) Price 4s. 6d, net.

Education and National Efficiency in Japan. In general character this useful volume resembles the The notice of my book " Dai Nippon, the Britain of the text-books already available for students of coal- | East,” which appeared in NATURE of December 1, directed mining. The work is, however, carried to a rather

attention to a nation from which much may be learnt at more advanced stage than has hitherto been considered

the present time, and it may interest your readers if I necessary for an elementary class-book, and chapters experience and observation. In the memorandum issued by

supplement your article by a few notes from my personal are given dealing with allied subjects, such as

Sir Norman Lockyer suggesting the formation of a British chemistry, mechanics, the steam-engine, and elec- Science Guild, it is stated that the people of this country tricity. The order of treatment differs from that do not manifest that interest in and belief in the power of usually adopted, the subjects dealt with being :- science which are noticeable among the peoples of the (1) geology; (2) structure of stratified rocks; (3) coal Continent or of America, and that, in spite of the efforts and coalfields; (4) search for coal; (5) sinking; (6) of many years, the scientific spirit essential to all true opening out; (7) miners' tools; (8) explosives; (9) progress is still too rare, and, indeed, is often sadly lacking methods of work; (10) working by long wall; (11)

in some of those who are responsible for the proper conduct methods of working by pillar and stall; (12) special Guild has been proposed with the view of attempting to

of many of the nation's activities. The British Science methods of work; (13) timbering ; (14) coal cutting by

remedy this evil, and to bring home to all classes the machinery; (15) mechanics; (16) steam; (17) gases; necessity of applying scientific treatment to affairs of all (18) ventilation ; (19) instruments; (20) lighting ; (21) kinds. winding ; (22) haulage; (23) pumping ; (24) surface The objects of such a guild have been attained, to a very arrangements; (25) coke making ; (26) accidents; and

remarkable degree, in Japan, not so much by the formation (27) electricity. This arrangement is not so logical of a special organisation for the purpose, as by the awakenas that adopted by the late Sir C. Le Neve Foster in his ing of the national consciousness to the necessity of keeping elementary work. For example, sinking with rock

in mind certain definite aims, and by the earnest cooper. drills is described before mining tools, coal-cutting ation of the various departments of Government, of scienmachinery before the elements of mechanics, and

tific associations, and of private organisations of many electric signals before electric terms are defined. The

different kinds. There is, indeed, a danger at the present brief chapter on coke making is hardly necessary, as

time in this country of too much importance being attached this subject is usually dealt with in metallurgical spirit which pervades them. Mr. Matthew Arnold, in one

to mere organisation and machinery, and too little to the treatises. It is doubtful, too, whether the chapters of his last official reports on elementary schools, pointed on chemistry, mechanics, steam, and electricity are out that " our existing popular school was far too little formsufficiently full to give an insight into the allied sub- ative and humanising, and that much of it to which jects, for the study of which excellent text-books are administrators point as valuable results is in truth mere available. The illustrations are clear and diagram- machinery;". This applies with far greater force to a great matic, and possess the advantage of having been

deal which has been done in recent years in the way of specially drawn for the book.

scientific and technical education. Instruction and know

ledge are too often confounded with education, and mere Bird Notes from the Nile. By Lady William Cecil.

machinery and organisation prevent the development of the

scientific spirit. Many of the men who are supposed to Pp. xii + 113; illustrated. (London: Archibald

have had a complete technical education are very poor Constable and Co., Ltd., 1904.) Price 25. 6d.

specimens of humanity, wanting in individuality and net.

character, devoid of all originality, and with a very narrow

view of the world. Some of them may manage to pile up Three claims to high commendation present them

fortunes for themselves, but they will do little to make their selves on the first glance at this elegant little popular country great. Even from a practical point of view, success work. In the first place, the numerous illustrations in any trade or profession does not depend so much on the are simply exquisite; secondly, technical names are amount of information which may have been crammed into banished from the text; and, thirdly, in the long list the learners' heads as is often supposed. It depends in. of species forming the appendix such names appear to comparably more upon their capacity for useful action than be correctly spelt, and are thoroughly up to date, even upon their acquirements in knowledge. All experience to the adoption of the so-called " Scomber scomber" proves that the spiritual is the parent and first cause of the system of alliteration. In her preface Lady William

practical, and especially the economic history of the Middle confesses that the notes were written originally solely Ages shows us that an ounce of manly pride and enthusiasm

is worth more than a pound of technical skill. for her children, who doubtless were desirous of

The recent history of Japan has emphasised this fact. possessing a memento of their parents' Nile trip, but While attention has been paid to details, the spirit which that friends persuaded her to offer them to the public. has animated the leaders of public opinion and action has The adoption of this advice is, in our opinion, fully been the chief cause of the great developments which have justified, and while the book has no doubt been found taken place. The complete study of this aspect of Japanese delightful by the young people of the family, it

national life would take us into many interesting psychocan scarcely fail to be a pleasant companion to the

logical discussions, but it is sufficient for our present pur. many bird-lovers who make a winter excursion up the

pose to note that the Japanese mind, unlike the British Nile. Although no attempt (and very properly) is made (which is strongly individualistic), is dominated to a very at technical descriptions of the various species while Japanese philosophy and their former social order were

At the same time, encountered during the voyage, such notes as are given

essentially communistic in their nature, still (contradictory are in most cases sufficient to render identification an as it may seem) their genius is individualistic, and they easy matter, to say nothing of the instances when this impress their personal qualities on their work, although is rendered self-evident by the illustrations.

they are willing to sacrifice results to a rigid organisation.

R. L. The outcome of it all is that the national consciousness is

directed to the attainment of national objects by men whose tails of these I must again refer to my book. The motive individual powers have been trained to make effective use underlying all the efforts is what I wish chiefly to emphasise. of western science, and the results have been simply Shortly after the Emperor succeeded to the throne, he issued wonderiul.

a proclamation which contained the following sentence :These results have been most apparent in the operations “ Knowledge and learning shall be sought after throughof war. It was the sound of the cannon on the Yalu River, out the whole world, in order that the status of the Empire in the war with China ten years ago, which awoke Europe of Japan may be raised ever higher and higher.' The and America to a knowledge of the fact that a new nation recent history of Japan is the most striking illustration of had been born in the Far East, and which at the same time the influence of a wisely directed system of education on started many of the political problems which have led up national affairs when those who are responsible for it are to the present war with Russia. That war, whatever its infused with high national ideals. ultimate results may be, has shown that the Japanese have At the same time it should be noted that some of the not only been able to take full advantage of the applications most thoughtful and influential men in Japan doubt whether of western science, but that they have been animated by the official system of education is likely to lead to the best the spirit of old Japan, which has made them regardless results. They feel, like Matthew Arnold, that too often the of personal sucrifices. The Army and Navy have been machinery and organisation receive more attention than the organised and worked on scientific methods, and with a real education, and, moreover, they dislike the idea of all conpleteness of arrangements which has won for them the educational institutions being of the same type. Probably admiration of all impartial critic Their intense patriotism the most influential educationist Japan was Yukichi has caused them to perform deeds of daring which are Fukuzawa, and he never failed to point out the possible unequalled in the history of war, while their skill in strategy evils which are likely to arise from a too strictly official and in the applications of the latest scientific methods to routine. His own college, the Keio Gijuku, has been a all they have done has made them almost uniformly great school for statesmen, lawyers, and public men, and Successful in their operations. They have demonstrated the many of the leading men in Japan have been his pupils. importance of the work of the engineer. The railways Count Okuma, the distinguished statesman, has also estabwhich have been built in Japan have been fully utilised to lished what is essentially a private university, and there are convey men and materials, and the ships to transport them many other schools of different kinds, all of which suppleoversea. The telegraphs have been used to communicate ment the Government institutions. Even in the technical instructions and to keep the authorities informed regarding and professional establishments, however, attention is not movements and requirements. The dockyards and ship- confined to the subjects required for strictly utilitarian purInuilding yards have been ready to undertake repairs, and poses or for examinations; the first object is to train men the arsenals and machine shops to turn out war material who will be able to serve their country, in the fullest sense of all kinds, as well as appliances which aid operations in of that term. Many discussions are now being carried on the field. Light railways have been laid down on the way with regard to the future of education in Japan, and the to battlefields, and wireless telegraphy and telephones to general tendency of these was indicated a short time ago convey instructions to soldiers ; in short, all the latest appli- by a distinguished Japanese author when he said, “No eations of mechanical, electrical, and chemical science have system of education which is not based on sociological conbeen freely and intelligently employed.

ditions can be thoroughly successful, and therefore a study The ships of the Japanese Navy are probably the best of ethnology, sociology, and of evolution generally is absoillustrations of the Japanese methods of procedure. In naval lutely essential to a thorough understanding of the matters they accepted all the guidance the western world educational questions awaiting solution." The Japanese could give them, but at the same time they struck out a are now face to face with many problems which confront line of their own, and the feet which they have created is all industrial nations, and it is to be hoped that, having unique in the character of its units. British designs have organised their education generally, and in some respects in many respects been improved upon, with the result that

given an example to western nations, they will go a step they have obtained in their latest ships many features which further and show that it is possible to combine industrial have won the admiration of the naval world. The inven- development with the welfare of all classes of the comtions and improvements which have been made by Japanese munity. officers, engineers, and scientific men disprove the charge The chief lessons which the British Science Guild has to which is very often made, that the Japanese have no learn from Japan is that if it is to be of any real influence originality. Even in the matter of pure science Japanese in the life of the Empire, the term science must be used in investigators have shown that they are able to take their its broad sense, as including all knowledge required for places among those who have extended the borders of individual and collective life, and that all efforts must be knowledge. The memoirs and papers published by Japanese guided by a consciousness of the real aims of national life. students and teachers, both on scientific and literary sub- Glasgow, December 6.

HENRY DYER. jects, will bear very favourable comparison with those of any other country, and while no Japanese Newton, Darwin, or Kelvin has yet arisen, there are men connected with

The Heating Effect of the y Rays from Radium. Japanese universities and colleges of whom any learned In a recent communication to the Physikalische Zeitinstitution in the world would have no reason to be ashamed. schrift (No. 18, September) Paschen has described some

I must refer to my book for details of the developments experiments which indicate that the rays from radium which have taken place in engineering and industry. supply a large proportion of the total heat emission. It Suffice it to say that roads and rivers have been improved, is known that the heating effect of radium when surrounded railways to the extent of between four and five thousand by an envelope of sufficient thickness to absorb both the miles have been constructed, a large mercantile marine has a and B rays is about 100 gram calories per hour per gram. been created, docks and harbours have been made, tele- Paschen, however, found that if the radium was surrounded graphs and telephones are in use all over the country, excel- by a sufficient amount of lead to absorb completely the lent postal arrangements are in operation, and there are q rays the heating effect was increased 2-26 times. . This few departments of mechanical and chemical industry in large heating effect of the y rays was so unexpected, and which there are not many establishments doing very of such great importance in connection with the nature efficient work. The result of it all has been that commerce of these rays, that we decided to verify this result by an has been immensely extended, and the financial resources independent method. In Paschen's experiments, the heatof the country developed in such a manner as to enable ing effect was determined in a special Bunsen ice caloriJapan to take her place among the powerful nations of the meter, in the central tube of which the radium, surrounded world.

by a lead cylinder about 4 cm. in diameter, was placed. At the root of all these developments has been the very In order to correct for the natural melting of the ice complete system of education which has been established mantle a differential method was employed. In our exin the country. Elementary schools are to be found in every periments we decided to use a differential air calorimeter, district, and secondary and technical schools in populous similar to the one described in our previous work on the centres, while the universities of Tokyo and Kyoto supply the heating effect of radium and its emanation (Phil. Mag., highest training required for the national life ; but for de February). In each flask of the differential air calorimeter there was placed a narrow glass tube, closed at the lower Generally Mr. Kearton conveys his information in end and extending to about the centre of the flask. The simple language, but he is very prone to speak of a radium bromide weighing 23.7 milligrams was enclosed bird picking up food between its two mandibles when in a small metal capsule supported by a thread, and was it would be “ shorter, simpler, and better understood " inserted alternately in the glass tubes. The flasks, (to quote from a well known Bar story) if he said beak. originally at atmospheric pressure, were immersed in a

Apparently old fables connected with animals die hard, water bath kept in a constant temperature room, and were connected by a xylene tube which served as a manometer.

for, according to the author, many young people at the The heating effect was measured by the movement of the

present day believe that a wren is a female robin, and xylene column, observed by a telescope with micrometer that male robins lose their red breasts in summer, eye-piece, and the scale was calibrated by a small heating coil of approximately the same dimensions as the radium. Two sets of experiments were carried out, in one of which the ends of the glass tubes were inserted in lead cylinders 3 cm. in diameter and 3 cm. high, and in the other with aluminium cylinders of exactly the same dimensions.

The lead envelope absorbed more than half the y rays, while the aluminium absorbed only a few per cent. ine readings were found to be very steady and consistent, but no appreciable difference in heating effect could be detected in the two experiments. As a check, the heating coil was employed in both experiments to calibrate the readings, the means of which agreed to about i per cent.

According to Paschen's results, the heating with the lead cylinders should have been at least 50 per cent. greater than with the aluminium cylinders. In our experiments we could not have failed to detect a difference of 5 per ceni. We conclude from this that the y rays do not supply more than a small percentage of the total heating effect of radium.

E. RUTHERFORD.

H. T. BARNES. Fig. 1.-Young Dunlins in their natural surroundings. From Kearton's McGill University, December 1

“Cock Robin." (Cassell and Co.). Singularities of Curves.

These and other old wives' legends Mr. Kearton does

his best to replace by accurate and interesting accounts The compound singularities of algebraic curves offer a wide field for discussion, but the naming of the simple

of the mysteries of bird-life. singularities has not yet been placed on an entirely satis

The best (if there can be a best where all is so factory footing. The latter consist of (1) point singulari interesting) of the five chapters are the two on nestties, which are nodes and cusps ; (2) line singularities, which ing and the clamour of chicks, both being illustrated I prefer to call bitangents and inflections. Mr. Basset calls by a number of photographs of nests and young birds. them double and stationary tangents; but if this is done, Very graphically does the author bring out the remarksymmetry requires that the point singularities should be able difference in development at the date of hatching called double points and stationary points, and this is not between a young sparrow, for instance, and that of admissible, because the phrase double points (as now used) a woodcock, and he also shows how much this differincludes cusps as well as nodes. If a curve has a double

ence depends on habit, a young skylark showing a point Mr. Basset calls it autotomic (self-cutting); but this

somewhat intermediate stage. Very striking are the term is incorrect when all the double points in the curve are cusps (as in the cardioid), for the curve does not then

two photographs here reproduced, the one showing cut itself. If it is really desirable to have a means of dis

young dunlins skulking amid their native covert, and tinguishing curves that have nodes or cusps from those that have none, they may perhaps best be described respectively as curves with or without point singularities. December 8.

T. B. S.

[graphic]
[graphic]

A CHRISTMAS BIRD-BOOK."
T!
HE success which attended his last children's bird-

book has induced Mr. Kearton to cater once more for the wants of young people interested in the animal life around them, and the result is the present charming little volume, illustrated, as usual, by reproductions from photographs taken direct from nature by the author and his brother. In the guise of a narrative told by “ Cock Robin " to his offspring, the author has contrived to convey in his own inimitable manner a vast store of information concerning bird-life, interspersed with observations relating to other animals. Although, as already said, intended primarily for Fig. 2.-The same birds in unnatural surroundings. From Kearton's juvenile readers, the volume contains a certain

"Cock Robin." (Cassell and Co.) amount of information which may be new to some of their seniors, including those to whom natural history, the other the same birds removed to an uncongenial is not an unknown study. For instance, until we environment. learnt it from Mr. Kearton's pictures, we ourselves “Nature-teaching "could not be conveyed in a better were ignorant of the marked and easily recognised manner, or in one less free from affectation and difference between the foot-prints of a rabbit and those faddism, and we trust that the “Kearton annual" of a hare, despite the number of times they have come will enjoy the extensive patronage that it certainly under our notice in the snow.

merits among those on the look-out for suitable 1 "The Adventure of Cock Robin and his Mate." By R. Kearton.

Christmas presents for their young friends. Pp. xvi +240 ; illustrated. (London : Cassell and Co., Ltd., 1904.) Price 6s.

R. L.

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