Slike strani
PDF
ePub

THE DAYLIGHT FIREBALL OF JULY 5.

VERY large meteors apparently exhibit a preference

for the early evening hours. The fireball of March 28 last came at 7.48 p.m., and a great number of corroborative instances might be cited. The majority of these bodies travel with comparatively slow motion over extensive arcs, and are directed from radiant points in the western region of the heavens.

On Monday evening, July 5, at 8h. 30m., a few minutes after sunset, a splendid fireball passed from west to east in a long and nearly horizontal flight across the southern sky. The weather was generally clear over the south of England at the time, and thousands of observers were fortunate in catching a sight of the meteor as its nucleus disintegrated into a series of glistening balls strung on a fiery cord.

The spectacle was viewed by persons who sent in reports from Gloucestershire, Dorset, Hants, Essex, Somerset and Surrey, but the descriptions are rather at

time. No stars were visible to which the path of the object might be referred. Yet, though daylight was so strong, the meteor brightly illumined the sky and attracted people to look upwards to ascertain the cause.

Mr. W. G. Wallace, of Broadstone, Dorset, writes that his sister saw the meteor in a S.S.E. direction, altitude about 30°. It disappeared over E. by S., altitude 20°. The object presented a brilliant mass of greenish-yellow light, moving slowly, and near the end of its flight it divided into two portions.

Mr. A. G. Pile, of Old Sodbury, Gloucestershire, observed the meteor moving from S.W. towards E. in from four to five seconds. It emitted a bluish-yellow flame, and looked like a large sky-rocket.

Mr. Dick, of Purley, Surrey, states that it quite lit up the sky, and travelled from S.W. to E. by S., about 20° high. It split into two large fragments early in its flight. What specially struck him was the horizontal course, duration about 13 seconds.

Mr. W. J. Allen, of Thornbury, Glos., saw the bright light of the meteor traversing the sky in a horizontal direction from S.W. to E. When first noticed it apparently consisted of three electric balls, but at the end only two could be discerned.

Mrs. L. E. Butter, of Bishops Waltham, Hants, reports that her son, when sitting in the garden, called her to see a bright, comet-like appearance travelling from S.W. to eastward. There was a secondary head merging into the tail. The object finally burst like a rocket.

Mrs. H. I. W. May, of Chadwell Heath, Essex, relates that her daughters saw a brilliant star in the south going from west to east. While watching it the head divided into three stars and then disappeared.

At Bristol the meteor passed from W. of S. to E.S.E.; the angle of descent was slight, motion rather slow, and the nucleus consisted of two balls of fire, the leader being the largest. There was a profuse emission of sparks as the object sailed along, and the duration for the section of the flight which came under observation was six seconds.

Mr. E. W. Barlow writes that at Bournemouth the phenomenon was remarked by various people who could not, however, give exact particulars of the event. When passing due S. the altitude was 40° to 45°, and the motion horizontal. The direction was from west to east.

I have been in correspondence with the various observers and elicited much further information, which has enabled me to derive the real path of the meteor. But the result may possibly require revision on the basis of additional records :

[merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][ocr errors][merged small][ocr errors][merged small][ocr errors][merged small][merged small][merged small]

THE MATERIAL BASIS OF EVOLUTION. THE Origin of Single Characters as Observed in Fossil and Living Animals" forms the subject of an illuminating essay in the American Naturalist for April, by Prof. H. F. Osborn. Since it contains some trenchant criticisms on recent attacks on the evolution theory, and on Darwin's work, it is likely to be much discussed in the immediate future.

The main purpose of his address is to insist on the importance of single characters, or "least characters," as indices of the trend of evolution rather than on the sum of the indefinite number of single characters which make up the individual. "In a sense," he remarks, "the species, subspecies, and variety, and even the individual, is not a zoological unit, whereas the character,' when narrowed down to the last point of divisibility, seems to be a unit. . . and a very stable one, with certain distinctive powers, properties, and qualities of its own." This conception of the individual as a complex of separable and independently variable units represents a view which has been gaining ground for some time past.

[ocr errors]

But Prof. Osborn attempts to systematise this newer conception of the factors to be reckoned with in studying the elusive and complex phenomena associated with the transformation of animals. He distinguishes two aspects of this process-the study of the birth and development of proportional, and of numerical characters. Those of the first category he defines as universal and abundant; they are such as distinguish species and subspecies one from another, and may be germinal and therefore heritable, or merely somatic, due to environmental influences; while numerical characters, on the other hand, are solely germinal.

As numerical characters he cites the number of the teeth and of their cusps, the number of toes and of vertebræ, and so on, such being relatively stable characters which may be shared in common between a large number of species and genera.

[ocr errors]

That no hard and fast line can be drawn between proportional" and "numerical" characters Prof. Osborn himself realises, for he uses as an illustration the reduction of the digits, as in the case of the evolution of the horse's foot. Hence it seems difficult to accept his dictum that proportional and numerical characters are due to a different series of direct causes. Rather they seem to be merely measures of degreequantitative and qualitative.

Towards the latter part of his essay he aims a blow at the Mendelians, and remarks that "If the student of genetics abandons the natural and the normal for the unnatural and the abnormal and sticks solely to his seed pan and his incubator, he is in danger of observing modes of origin and behaviour of characters which never have, and never will, occur in

Το

nature." Nor is he less positive that there is no evidence whatsoever in support of the theory that "species" may arise from fortuitous, saltatory characters. This is one of the traditions, he tells us, of the master mind of Darwin that we must abandon entirely. But this, surely, is yet at least a debatable point. Prof. Osborn apparently is convinced that all characters must run the gauntlet of selection. attempt to defend such a position is to court disaster. As Prof. Osborn himself maintains, the individual is to be regarded as a complex of unstable units, and this instability is expressed in a tendency to development along new lines of growth. Each unit, in short, has its own individuality and potentialities of development, which are controlled, in the first instance, by the immediate environment-the neighbouring units of the organism-just as the organism as a whole is in turn controlled by the external environment, or by "selection." Where the incidence of the struggle for exist ence falls lightly, such units may give rise to hypertrophied outgrowths, as, for example, in the train of the peacock, or in the huge wings of the Argus pheasant where the struggle for existence is severe, ornament and other exuberances of development are suppressed.

Finally, in regard to natural selection and its relation to the origin of characters, Prof. Osborn remarks that we know nothing; hence he seems disposed to regard with something like approval the recent enunciation of Prof. Bateson that we may have to forgo the theory of the addition of germinal factors, or determinants, and substitute the theory of variation by loss of factors.

[ocr errors][merged small]

This theory of evolution by "loss" captivated many, but surely when the phenomena on which this is based are carefully examined it will be found that the phrase 'evolution by loss" amounts to no more than an emphasis of the fact that the evolution of new types is but a more striking phase of the evolution of species. For with types, as with the species which they embrace, the material basis of evolution is afforded by Prof. Osborn's "allometrons or "proportional characters."

UNIVERSITY AND EDUCATIONAL

INTELLIGENCE.

EDINBURGH.-At the summer graduation on July 8 Sir William Turner, the Vice-Chancellor, who presided, said the University roll of honour now contains more than 4000 names. Among the honorary degrees conferred were the following:-Doctor of Laws Sir Robert Blair, education officer, London County Council; Prof. W. A. Herdman, University of Liverpool; and Prof. Arthur Thomson, University of Oxford.

THE Department of Agriculture and Technical Instruction for Ireland has issued as a pamphlet a descriptive account of the Irish Training School of Domestic Economy. The school is situated at St. Kevin's Park, Kilmacud, Stillorgan, Co. Dublin. The premises stand in grounds of about three acres, in one of the finest situations in South County Dublin. The house provides ample accommodation for the staff and students, in addition to class and recreation rooms. The school is a residential institution, maintained by the Department of Agriculture and Technical Instruction for Ireland, for the purpose of training teachers of domestic economy, and also for providing a training in household management for girls who have received a satisfactory education. The work of the school comprises two courses of instruction-a course of instruction extending over one year in household management, the object of which is to train girls

for the management of their own homes, and a further two years' course of training for teachers of domestic economy.

We have received a copy of the report of the council to the members of the City and Guilds of London Institute for the year 1914. The results in the department of technology show that the year 1913-14 was a record year, so far as regards attendance at classes in technology. During the session 5049 classes in technological subjects were registered by the institute 55,996 students, showing an increase of 1486 on the in 321 towns, and these classes were attended by numbers in the previous year. At the examinations, 23,119 candidates were presented in technology, showing an increase of 1241, and by including candidates from India, from the overseas Dominions, and from other parts of the Empire, and for special subjects other than technology, the total number of examinees severely in this as in other departments of the instiwas 26,776. But the effect of the war has been felt tute's work. Four appendices contain detailed reports of the dean on the City and Guilds (Engineering) College, of the principal on the City and Guilds Technical College, Finsbury, on the City and Guilds South London Technical Art School, and on the work of the department of technology, in each case for the session 1913-14.

SOCIETIES AND ACADEMIES.

LONDON.

Physical Society, June 25.-Dr. A. Russell, vice-presiCondent, in the chair.-Sir J. J. Thomson : duction of electricity through metals. The discovery by Kamerlingh Onnes, that at the temperature of liquid helium some metals can exist in a state in which their specific resistance is less than one hundred thousand millionth part of that at o° C., appears to necessitate the abandonment of the ordinary theory of metallic conduction, as the experimental conditions prohibit the explanation of the phenomenon by an abnormal increase, either in the number or mean free path of the free electrons. The effects observed by Kamerlingh Onnes may, however, be accounted for by a theory of metallic conduction previously given by the author in "The Corpuscular Theory of Matter." On this theory the atoms of some substances contain electrical doublets-i.e. pairs of equal and opposite electrical charges at a small distance apart. The effect of an applied E. M.F. is to alter the heterogeneous distribution of the axes of these doublets by bringing them into partial alignment with the field. The function of the applied field is to produce the alignment of the doublets; the actual transference of electricity is effected by the large interatomic forces brought into being by the polarisation of the doublets. Thus, if the polarisation remains on withdrawing the applied E.M.F. the current will also remain.-Lieut.-Col. G. O. Squier: An unbroken alternating current for cable telegraphy. (1) The paper proposes a new angle of view in the method of transmission of signals in the submarine telegraph cable, and describes some apparatus for operating on the general principles involved. (2) An ocean cable is considered as a power line, and starting with the standard form of circuit which would be used in case it were required to operate an electric motor through an ocean cable, experiments are described to determine the minimum possible variations required in such a circuit to permit the alternating current received to be interpreted in dots, dashes, and spaces of the present alphabet. The uninterrupted alternating current used in transmission is operated on synchronously by the ordinary transmitting tape, so as to alter the im

pedance of the transmitting circuit at the instants when the current is naturally zero. Dots, dashes, and spaces are each sent by semi-waves of either sign, but of different amplitudes. The alternating current received may be read directly from the record made by a siphon recorder, or this current may be employed to operate a siphon Morse printer, by means of an adaptation of Muirhead's gold-wire relay, or a Heurtley magnifier and a local wire relay. (3) The voltage stress along an Atlantic cable when an alternator is employed is shown, and the transmitting impedance of such a cable is computed as the frequency varies. (4) A special form of cable dynamo to operate at frequencies from 4 to 10 was used in the experiments described. (5) The fundamental principle is developed of never metallically "breaking" the transmitter circuit, which permits of greater accuracy in balancing the duplex bridge.

EDINBURGH.

the

Royal Society, June 21.-Prof. Hudson Beare, vicepresident, in the chair.-Dr. A. Lauder and T. W. Fagan: The composition of milk as affected by increase in the amount of calcium phosphate in the rations of COWS. In these experiments the amount of calcium phosphate added was gradually increased to 8 oz. per head per day. No increase in the amount of phosphorus or of mineral matter in the milk could be detected, in agreement with the generally received opinion that within wide limits the composition of milk was little affected by the nature of the food fed to the cow.-J. Herbert Paul: A comparative study of the reflexes of autotomy. Self-amputation of limbs in the Decapod Crustacea is accomplished in various ways. Thus hermit crabs when removed from their shells usually respond to injury by plucking off the damaged limb with their claws. The "true" crabs possess a specialised mechanism by which limb is weakened at the breaking plane, SO that a very slight force can sever it. In lobsters, a special muscle, by violent contraction, weakens the limb along a groove in the third segment, and immediately the imprisoned limb is left in the grasp of the enemy. If the more highly developed mechanism is disorganised in certain species, the animal returns, as it were, to the ways of its ancestors, and attempts to amputate the injured limb by more primitive methods.-Dr. M. Young: A contribution to the study of the Scottish skull. The investigation was based upon a study of more than 700 skulls which have been for some years in the possession of the anatomical department of the University of Glasgow. The greater number were collected by W. K. Hutton, lecturer in anatomy, Queen Margaret College, and were obtained during the excavation of an old Glasgow burying ground. The skulls are in the great majority of cases West Scottish skulls. They are more dolichocephalic than the average of Sir William Turner's series of Scottish skulls, but resemble most closely those in this series which are derived from Renfrewshire. Comparison between the two series has been made by the ordinary method; and the Glasgow collection has also been examined by modern biometrical methods, and the variability, as well as the correlation of the West Scottish skull as regards many of its dimensions and characters, have been determined and compared with those found in other series of skulls. One hundred specimens in the collection were divided in the medial sagittal plane, and from a study of the sectorial diagrams it appears that certain values of features which have been regarded hitherto as of morphological importance in different races fall within the range of variation shown by the large homogeneous West Scottish series. The skulls are similar in type to the "Long Barrow" crania from the cham

bered caverns of Arran, described by Prof. Bryce, and the Whitechapel English series of crania described by Dr. Macdonnell. They are without doubt those of to descendants of the Iberian or Mediterranean stock T race who have remained in the West of Scotland and have been less influenced by the later brachycephale type than has been the case in the east of Scotland. Their mean values represent only a type of Scottish skull, but this type perpetuated in comparative purity in the present collection is that which, modified b various factors, has resulted in the diverse cranial form seen in Scotland at the present day.-Dr. Ashworth and Dr. J. Ritchie: The morphology and development & the free-swimming sporosacs of the hydroid gents Dicoryne; with description of a new species. The sporosacs of D. parthenopeia closely resemble those of D. conferta, except that they have a single tentacle, and the female sporosac bears only one ovum. The oocytes are differentiated and grow in the ectoderm of a blastostyle in the position which the sporosac will ultimately occupy; there is no migration of oocytes. The sporosac does not exhibit during development anv trace of medusoid structure; there is no evidence that this sporosac has undergone regression from the condition of a medusa or medusoid gonophore. The general structure of the colony of D. parthenopeia, the regenerative capacity of the stolon, the method of release of the sporosacs, and the early development of the egg are also described.

PARIS.

Academy of Sciences, July 5.-M. Ed. Perrier in the chair.-M. Giller: Lightning and telegraph lines. An analysis of certain features common to all telegraph posts struck by lightning, and a suggestion for avoiding damage by the introduction of a spiral resistance possessing self-induction.-Henri Pénau: Cytology of the Bacillus verdunensis. This new species has been found in water at Verdun, and has some properties in common with the coli bacillus, from which, however, it can be separated. Details of various stages ot growth are given.-M. Gard: A genus of Papilonacea, new for cyanogenesis.-Ed. Crauzel: The treatment of recent wounds by an expansible solution of iodine. The use of ether containing 5 per cent. of iodine in solution is suggested as offering advantages over the usual alcoholic tincture. It does not change in strength, and penetrates rapidly into wounds.-J. Cluzet: A simple method for the electrical examination of paralytics. The apparatus consists of a system of condensers, capacity from 0.01 to 12 microfarads. capable of utilising directly current from lighting mains. The use of the instrument in diagnosis is described.-A. Policard and A. Phélip: The first stages of the evolution of lesions in wounds caused by war projectiles, with some practical consequences. AD fragments of clothing must be removed from the wound at the earliest possible moment. Too free use of antiseptics may diminish the defensive reaction of the tissues in the neighbourhood of the wound.-M. Billon-Daguerre: A mode of producing thin sheets of liquids for sterilisation by ultra-violet light.

WASHINGTON, D.C.

National Academy of Sciences, presented 10 the Academy from April 15 to May 22.-C. G. Abbot, F. E. Fowle, and L. B. Aldrich: Confirmatory experi ments on the value of the solar-constant of radiation. Observations at Mt. Wilson from sunrise until ten o'clock, and records obtained by a recording pyrhelic meter attached to sounding balloons rising to the altitude of 24 km. confirm the value of 193 calories per square centimetre per minute previously obtained for the radiant energy received by the earth from the sun.-T. H. Goodspeed and R. É. Clausen: Varia

tion of flower-size in Nicotiana. During five years of study of the inheritance of flower-size in Nicotiana it has been found that the flower-size is not so constant as it has been assumed to be, but is affected by a number of conditions, some of which may not affect the length_and the spread of the flower in the same manner.-I. S. Kleiner and S. J. Meltzer: Retention in the circulation of dextrose in normal and depancreatised animals, and the effect of an intravenous injection of an emulsion of pancreas upon this retention. In normal animals the circulation possesses the ability to get rid readily of a surplus of dextrose injected intravenously. This ability is impaired in the absence of the pancreas, but can be temporarily restored by intravenous injections of pancreas emulsion. Such injections, moreover, are capable of reducing the hyperglæmia due only to depancreatisation.-T. H. Goodspeed: Parthenocarpy and parthenogenesis in Nicotiana. Mrs. R. H. Thomas found frequent cases of parthenogenesis in Nicotiana; but other experimenters have been unable to verify these results. The present investigation, conducted upon the particular strains of tobacco of which seeds were furnished by Mrs. Thomas, shows that in those strains parthenocarpy is a frequent occurrence, and that parthenogenesis is also peculiar to this variety.-R. H. Lowie: Exogamy and the classificatory system of relationship. The exogamous factor must have been a real cause in moulding the kinship terminology of at least some so-called classificatory system. This conclusion is reached by a study of the character of two Siouan tribes, the Crow and Hidatsa.-F. R. Moulton: Solution of an infinite system of differential equations of the analytic type. If the number of mutually gravitating bodies in the universe is infinite, and if beyond a finite number of them their initial distances from one another increase with sufficient rapidity as the number of bodies increases, there is a rigorous, though limited, solution of the problem of infinitely many bodies.-L. J. Cole and N. F. Kirkpatrick: A seven years' study of inheritance in pigeons leads to the conclusion that the normal ratio of the sexes of pigeons hatched is 105 males to 100 females; that the number of unisexual broods exceeds the number of bisexual broods; that there is no tendency for first-laid eggs to hatch males and second-laid eggs to hatch females; that there is a correlation between the time of hatching the second egg and that of laying the first; that the birds continue to sit beyond the normal period of incubation if the eggs do not hatch.-Alice Rohde: Vividiffusion experiments on the ammonia of the circulating blood. The generation of ammonia in shed blood occurs in the non-diffusible constituents of the blood.-C. P. Olivier: 126 parabolic orbits of meteor streams. Although the most important feature of this investigation is the calculation of 126 parabolic orbits, the most interesting result is the final proof of the connection of the Halley's and 7-Aquarid meteors. It is further concluded that radiants are not stationary.— C. Schuchert: The basal silurian formations of eastern North America. Medina, Cataract, and Brassfield are to be retained as names for independent marine faunas and formations.-B. M. Davis: A method of obtaining complete germination of seeds in Oenothera and of recording the residue of sterile seed-like structures. By sowing seeds upon pads of filter papers placed in Petri dishes and thoroughly soaked, and by keeping the culture at constant temperatures, rapid germination was obtained.-S. J. Bates: The osmotic pressure of the ions and of the undissociated molecules of salts in aqueous solution. The author shows how the partial osmotic pressures of the ions and of the unionised molecules can be calculated by thermo

dynamic principles from the freezing-points and conductance-ratios at a series of concentrations. The results show that in general the osmotic pressure of univalent ions is considerably smaller, and that that of the undissociated molecules is very much larger, than would be required by the osmotic-pressure law of perfect solutions.-T. Lyman: The extension of the spectrum beyond the Schumann region. The author has been able to reach the wave-length A600, and finds seven or eight lines in the helium spectra between A900 and 600, some of the lines being fairly strong. -A. S. King: Unsymmetrical lines in tube-arc and spark spectra as an evidence of a displacing action in these sources. The observed effects seem to be harmonised by considering as a necessary condition the presence of electrified particles moving at high velocities, these being produced in the arc and spark by the strong potential-gradients, and in the tube-arc by the large consumption of energy.-H. Blumberg: The factorisation of various types of expressions. The methods of E. H. Moore's "General Analysis" are applied to giving a uniform central theory for factorisation of different series of expressions.-G. E. Hale: The direction of rotation of sun-spot vortices. Of the two spots in the typical spot-pair the preceding spot in the low-latitude zone is counter-clockwise north, and clock-wise south, of the equator; corresponding to the direction of the rotation of terrestrial tornados. In high latitudes the signs are reversed, giving a result which is likely to prove significant in future studies of the sun.-G. E. Hale and G. P. Luckey : Some vortex experiments bearing on the nature of sun-spots and flocculi. Some of the phenomena of single and multiple sun-spots can be imitated by simple laboratory experiments, in which vortices are formed in a water-tank with an atmosphere of smoke above the water. Such experiments may assist in accounting for certain characteristic structures and motions of the solar atmosphere.

NEW SOUTH WALES.

Linnean Society, March 31.-Mr. A. G. Hamilton, president, in the chair.-Esben-Petersen: Australian Neuroptera. Part ii. This contribution deals with the Australian species of Myrmeleonidæ, comprised in fourteen genera; but the material available was insufficient for working out two of the large genera, Myrmeleon and Formicaleon. One genus and eight species are proposed as new.-G. I. Playfair: The genus Trachelomonas (Infusoria: fam. Euglenidæ, Stein). The extra-Australian records of the genus amount to a total of twenty-five published species of greater or less validity, and eight variations. Australian waters are very rich in forms of the genus, exhibiting a great variety of type.-E. Breakwell: The anatomical structure of some xerophytic native grasses. Grasses of eleven species, all but one from the Nyngan district, were studied.

April 28.-Mr. A. G. Hamilton, president, in the chair.-H. J. Carter: Descriptions of six new species of Buprestida (Coleoptera). The species described are referable to the genera Chalcotania, Buprestis, Bubastes (2 spp.), Neocuris, and Stigmodera; all, with the exception of one species of Buprestis from Dorrigo, N.S.W., from Cue, West Australia.-G. F. Hill: Northern-territory Termitidæ. Part i. This contribution to a knowledge of the Australian Termitida has been prepared from part of a large collection of Termites, and many field-notes compiled during the past two years, in what may be termed the coastal region of the Northern Territory. Fifteen species are dealt with in this paper, eight of which are described as new. With the exception of one species of Eutermes, which builds a very small mound, all

the termites found in the Territory collect the great bulk of the earth and sand used in their termitaria, upon the surface.-T. Steel: The feeding-tracks of Limax maximus, Linn.

CAPE TOWN.

Royal Society of South Africa, May 19.-Dr. L. Péringuey, president, in the chair.-A. Brown: The equivalent mass of a spring vibrating longitudinally. The paper deals with the allowance to be made for the mass of a spring when a weight attached to it is oscillating under gravity and the tension of the spring. The fraction one-third of the spring's mass is correct for great added weights; for very small weights the fraction is a little over two-fifths. The variation of this fraction is considered theoretically, and data supplied to give its value for any weight. Experiments are described confirming the theoretical results.A. W. Rogers: The occurrence of dinosaur bones in Bushmanland. Dinosaur bones were found in a well in Bushmanland at 112 ft. below the surface. The well is in an old valley cut in gneiss and filled in with local débris. It seems probable that the climate became dry while the dinosaurs lived there, and that since then the valley has been steadily filled up.S. H. Haughton: Description of the dinosaur bones from Bushmanland. The bones discovered by Dr. Rogers consist of a maxillary tooth and portions of the hind limbs and caudal vertebra of a medium-sized Ornithopodous Dinosaur. They are described under the name Kangnasaurus Coetzeei n.g. et sp., which is shown to have affinities with Camptosaurus and its allies, and with Mochlodon and Hypsilophodon. The form is certainly younger than Camptosaurus, but no estimate of its exact age is given-the evidence being considered to be insufficient.-C. K. Brain: The Coccidæ of South Africa. The paper, which is the first contribution to a catalogue of the Coccidæ of South Africa, deals with five subfamilies, viz. :Pseudococcinæ, Orthesiinæ, Coccinæ, Monophlebinæ, and Margarodinæ. Sixty-three species and two varieties are described, of which number thirty-two are here dealt with for the first time.-J. S. v. d. Lingen: A note on the molecules of liquid crystals. The object of the paper is to show the effect of bi-prisms on the Laue spots. Experiments carried out with prisms of NaCl show that the spots are fluted," and that the central spot is elliptic instead of circular. 60° and 179° bi-prisms show this phenomenon, especially when they are rotated through a small angle.-J. S. v. d. Lingen: The "lines" within Röntgen interference photographs. The author holds that these lines are due to the ruptured surface, which will most probably resemble an echelon grating. Sodium chloride, quartz, silicon, and magnesium hydroxide photographs are described. These show "irregular spots" under certain conditions.

66

BOOKS RECEIVED.

Arithmetic. By C. Godfrey and E. A. Price. Parts i., ii., and iii. Complete. With Answers. Pp. xiii+ 467. (Cambridge: At the University Press.) 45.

Typical Flies: a Photographic Atlas of Diptera, including Aphaniptera. By E. K. Pearce. Pp. xii+47. (Cambridge: At the University Press.) 5s. net.

Citizens To Be a Social Study of Health, Wisdom, and Goodness. By M. L. V. Hughes. Pp. xvii +331. (London: Constable and Co., Ltd.) 4s. 6d.

net.

The Natural History of the State: an Introduction to Political Science. By Prof. H. J. Ford. Pp. viii+ 188. (Princeton, U.S.A.: University Press; London: Oxford University Press.) 4s. 6d. net.

Ship Form, Resistance and Screw Propulsion. By

G. S. Baker. Pp. vii+245. (London: Constable ant Co., Ltd.) 12s. 6d. net.

Plain and Reinforced Concrete Arches. By Prof. ! Melan. Translated by Prof. D. B. Steinman. P: x+161. (New York: J. Wiley and Sons, Inc.; Le don: Chapman and Hall, Ltd.) 8s. 6d. net.

A History of British Mammals. By G. E. H. Bar. rett-Hamilton and M. A. C. Hinton. Part xvi. (London: Gurney and Jackson.) 2s. 6d. net. Introduction to Heat. By A. R. Laws and Dr G. W. Todd. Pp. x+212. (London: Mills and

Boon.) 2s. 6d. Scottish National Antarctic Expedition. Report on the Scientific Results of the Voyage of s.y. Scotia during the Years 1902, 1903, and 1904, under the Leadership of Dr. W. S. Bruce. Vol. iv. Zoology. Parts ii.-XX. Vertebrates. Pp. xii +505 + plates (Edinburgh: The Scottish Oceanographical Labora tory.) 50s.

Plane Geometry. By G. St. L. Carson and Prof. D. E. Smith. Part i. Pp. vi+266. Part ii. Pp vi+259-482. (London and Boston: Ginn and Co.) 2s. 6d. each part.

Elements of Algebra. By G. St. L. Carson and Prof. D. E. Smith. Part ii. Pp. v+325-538. (London and Boston: Ginn and Co.) 2s. 6d.

[blocks in formation]
« PrejšnjaNaprej »