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of races, species, and genera, while the first stage the this Relation that have taken place during the last Fifty larter corresponds to De Vries's and the second to Mendel's

Years has been published in the series of Drapers' Commutation. The Rev. E. Wasmann, in the second article, pany Research Memoirs (Studies in National Deteriordiscusses the comparatively recent development of new ation). Mr. Heron takes as his starting point the legitispecies of “commensural" beetles of the family Staphi- mate birth-rate for the different districts in London for linidæ in the nests of ants and termites. In the black and the years 1851 and 1901, and proceeds to calculate for each red beetles of the genus Dinarda, for example, there are year the correlation between this and various measures of races or species corresponding to the various races their social and economic conditions. By this method he species of ant with which they are associated, and as the shows conclusively that in both these years a low birthdifferentiation of the ants appears to be comparatively rate is associated with satisfactory conditions and a high recent, that of the beetles must, a fortiori, be still more one with poverty and improvidence, but that in 1901 this so. In the third article Maria Countess von Linden de- coincidence is far more strongly marked than in 1851, and scribes certain very remarkable variations in the shape and that whereas in the middle of the last century it could colour of the wing-scales of the swallow-tail butterfly be more than accounted for by the fact that the wives of Papilio podalirius during the pupa-stage as the effect of the upper classes marry at a later age than those of the external influences. It is noticeable that the scales on the lower, at the present time this factor is only responsible orange spot differ from those of the rest of the wing. for about half the difference. It is perhaps unfortunate The basilar membrane in the ear of parrots, in connec- for Mr. Heron that his paper has appeared after two tion with Helmholtz's resonance-theory, forms the subject others dealing with the same subject (Newsholme and of the concluding article, by Mr. A. Denker.

Stevenson, and G. U. Yule, Journal of the Royal StatisThe contents of Nos. 1 and 2 of vol. xxviii. of Notes

tical Society, vol. Ixix., part i.), as his methods are very from the Leyden Museum are largely devoted to the de

different from, and his conclusions quite independent of, scription of new genera and species, a number of these

either of them. But owing to the striking way in which being described by Mr. G, Ulmer in a paper on

these three important papers confirm and supplement one European trichopterous insects. Of more general interest another, it may be to the advantage of the public that they is the description, by Dr. E. D. van Oort, of a

should have appeared in the same year, for warnings of bird-of-paradise (Neoparadiseа ruysi) from New Guinea,

this nature have more chance of obtaining a hearing when representing a generic type by itself, and also Dr. they are given simultaneously from different quarters. Jentink's separation of the large duiker antelope of Rhodesia from the West African Cephalophus sylvicultor,

In the Journal of the Franklin Institute of Philadelphia

(vol. clxii., No. 1) Mr. Clifford Richardson gives an exunder the name of C. coxi.

haustive series of analyses of the petroleums of North THE New Zealand fern-bird (Sphenoeacus punctatus) | America, and compares the character of those of the older forms the subject of the first article, by Mr. J. C. M'Lean, and newer fields. in the July issue of the Emu, while in the second paper Mr. H. S. Dove gives notes on a number of New Zealand

A very simple and convenient method for calibrating birds, inclusive of introduced species. In a later com

thermometers for use in the determination of freezing points munication Mr. E. Scott contributes some interesting in

of aqueous solutions is described by Messrs. Richards and formation with regard to Dampier's observations

Jackson in the Zeitschrift für physikalische Chemie, 1906, Australian birds made during the voyage of 1689. Mystery

lvi., 362. The thermometer to be tested is immersed in attaches to the meaning of the term "gladdens," which

a mixture of powdered ice and water contained in a Dewar the great navigator employed to designate certain birds vessel, and hydrochloric acid is then added until the requiassociated with oyster-catchers and cormorants.

site temperature has been attained. The true temperature

is determined by the concentration of the acid solution in The whole of vol. xxvii. of Notes from the Leyden equilibrium with the ice, and this can be ascertained from Museum is occupied by Miss C. M. L. Popta's description the table given by the authors, in which acid concentrations of the fishes collected during Prof. Nieuwenhuis's expedi- corresponding to temperatures between o° C. and -5° C. tions to central Borneo in 1898 and 1900. The collection are recorded. contained a large number of new forms, which have, however, for the most part been named in previous communi

In a previous measurement of the relative proportion cations. The more important species are illustrated by of radium and uranium in radio-active minerals, a neutral photographs from original specimens.

solution of radium bromide was employed as standard. It

has since been observed, however, that such neutral soluSEASIDE natural history, illustrated with a number of

tions gradually deposit some of the active substance on excellent photographic plates (in some cases reproduced

the walls of the containing vessel, and this has made a from Johnston) of zoophytes, &c., occupies a prominent

new determination of the proportion of radium to uranium position in the July issue of the Museum Gazette. The

necessary. The number now found by Rutherford and addition of a large education museum to the “garden Boltwood (American Journal of Science, iv., 22 [127], pp. city" at Letchworth is strongly advocated.

1-3) for the quantity of radium associated with i gram Is its report for 1905, published in the August issue of of uranium is 3.8 x 10-' gram, which is about one-half that Nature Notes, the Selborne Society takes occasion to refer

obtained in the first experiments. to the necessity for more active workers and larger funds

In the Journal of Physical Chemistry, 1906, vol. X., if its objects are to be fully and efficiently carried out. The enclosure at Ealing for the protection of birds is re

P. 445, Messrs. Carveth and Magnusson give an interesting

account of the evolution of the apparatus for the determinported to have been a marked success during the nesting

ation of the boiling points of solutions for the purpose of season.

molecular weight measurements. The advantages and disA PAPER by Mr. David Heron On the Relation of advantages of the various types are discussed, and a new Fertility in Man to Social Status, and on the Changes in form of apparatus is described, the distinctive features of

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which are a separate boiling flask and a return condenser is a mine of information, containing as it does papris un provided with mercury trap. With this apparatus the discovery of “ Terra Australis," the physical configursmeasurements can be made very quickly, and the parts tion, the geological formation, the meteorology, vegetation. liable to break are easily replaceable.

timbers of commercial importance, fish and fisheries, and

fauna of New South Wales, besides much information of In the same journal Mr. R. C. Snowdon shows that

statistical importance. The volume is illustrated by on metallic lead can be electrolytically deposited in a satis

twenty-eight well-executed figures, and should be ven by factory and adherent condition from an acidified solution

all who are specially interested in the State under review. of lead acetate. This result is attained by employing a rapidly rotating kathode and a virtual current density of The twenty-sixth annual report of the Manchester 1.5 amperes per square decimetre, and adding about i gram Microscopical Society, which has just been issued, tells of of gelatin to a litre of the solution. In an investigation continued progress. The address on precious corals de of the behaviour of ferromanganese anodes in solutions of livered by Prof. S. J. Hickson, F.R.S., as president, is caustic soda, Mr. G. R. White finds that permanganate is

to be found in the volume, as is also an illustrated paper formed irrespective of the current strength and the concen- by Mr. M. L. Sykes on animal coloration. tration of the solution. Metallic manganese yields permanganate at high current densities, but manganous

The seventh annual report of the Museum and Art hydroxide is only oxidised to dioxide. The electrolytic

Gallery of Plymouth is of an encouraging nature. During formation of permanganate is therefore a direct reaction,

the year ending with March last many interesting additions the lower oxides not being formed as intermediate products.

were made; the public lectures on subjects connected with

the work of the museum were, it is stated, on the whole We have received from Messrs. Adam Hilger, Ltd., a decidedly successful. The museum and gallery were visited copy of their “ List A" of spectroscopes and spectroscopic during the period under review by 30,760 persons. accessories. This list contains descriptions and illustrations

A NEW (the second) edition of " The Geology of the of the numerous specialities manufactured by the firm, and

English Lake District, with Notes of the Minerals," by should be consulted with interest by all workers in spectro

Mr. J. Postlethwaite, has just been issued by G. and T scopy. The spectroscopes, spectrographs, and accessories

Coward, Carlisle. The little book has been revised and of especial interest are too numerous to be referred to

additional lists and plates of fossils have been added, and here, but mention may be made of the fact that the firm

the section on the Mollusca of the Skiddaw slates has fren is now prepared to supply the strips of plane parallel

rearranged. glass, up to 300 mm. by 40 mm., used in the Lummer and Gehrcke parallel plate spectroscope described in the The current number of the Monthly Magazine contains Annalen der Physik, vols. x. (1903) and xx. (1906). These

a very readable account, by Mr. H. W. Strong, of the strips may be used with any ordinary spectroscope of suit

evolution of the turbine, entitled * The Coming of the able size, but the firm will be pleased to quote prices for

Turbine"; it has also an interesting paper by Mr. A . specially designed instruments.

Rees on a moorland sanctuary.

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The edition of the Japanese Pharmacopeia, which has been in preparation for some considerable time, has now been completed, and will be issued shortly.

OUR ASTRONOMICAL COLUMN. Among the alterations in it is the substitution of Japanese ASTRONOMICAL OCCURRENCES IN SEPTEMBEK :characters for the names of drugs and chemicals for the Sept. 1. 14h. 42m. to 15h. 46m. Moon occults 1 Aquari Chinese forms hitherto used.

(mag. 4'3).

15h. Saturn in conjunction with Moon. Saturn A New magazine, entitled the University Digest, is

0° 34' N. announced for publication by the University Research 4. 13h. Mercury in conjunction with Mars. Mercury

0° 10' S. Extension of Chicago. Its aim (to quote from the pro

15b. Saturn in opposition to the Sun. spectus issued) is to keep before its readers the ideal

8. Predicted date of perihelion passage of Finlay : phenomena that distinguish the modern, the greatest of

comet. world-epochs,” and the intention of its promoters is to 9. 14h. 27m. to 14h. 430. Moon occults a Tauri represent the results of scientific research in religion,

(Aldebaran, mag. 1'1). philosophy, and the social and natural sciences. The

10h. 47m. Minimum of Algol (B Persei).

Vesta o N. of star 105 Aquarii (mag. 47). periodical will be issued at monthly intervals from

Vesta (mag. 6.5) in opposition to the Sun. September next, excluding the months of July and August.

15. Venus,

Illuminated portion of disc = 0514;

Mars =0'989. THE Proceedings and Transactions of the Nova Scotian

16. Saturn. Major axis of outer ring = 44° 33, minor Institute of Science for the session 1903-4, just received,

axis =4":15. contains many papers of value. The address of the presi

Ioh. Venus at greatest elongation, 46° 29' E. dent-Dr. H. S. Poole dealt with the progress of the 23

nih. Sun enters Libra, Autumn commences. institute and the application of science to mining, and

29.
ilh. 29m.

Transit (egress) of Jupiter's Sai. III. among other communications in the volume we notice the

(Ganymede).

30. 2h. 3om. Minimum of Algol (8 Persei). following :-the earthquake of March 21, 1904, in Nova Scotia, by Prof. J. E. Woodman ; swim bladder of fishes

Discovery Of A New Comet (1906).–A telegram frm

the Kiel Centralstelle announces the discovery of a nem a degenerate gland, by Prof. E. E. Prince; and determin

comet by Herr Kopff at the Königstuhl Observatory in ation of elements of terrestrial magnetism at Halifax, August 22. Nova Scotia, August, 1904, by Prof. S. M. Dixon.

Its position at 14h. 17m. (Königstuhl M.T.) on the ti

of discovery was R.A. = 22h. 49m. 325., dec. = +10* ?;. The official year-book of New South Wales for 1904-5 and the amount of its daily movement was found to be has just reached us. It is edited by Mr. W. H. Hall, - 44s. in R.A. and -2' in declination. Unfortunatele on acting statistician to the State of New South Wales, and idea of the connet's brightness is given.

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A second telegram from the same source states that the eye-piece is analogous to one described by Dawes in vol.

observed at Hamburg by Herr Graff on xxi. of the Memoirs of the Royal Astronomical Society, August 23, its position at 13h. 11.3m. (Hamburg M.T.) but as no one seems to have used this for the study of being R.A. =22h. 48m. 53:55., dec. = + 10° 21' 7".

minute details in sun-spots, Prof. Ceraski describes the From this it is seen that the comet is apparently in the one he is now using. svastellation Pegasus, a little to the north of a Pegasi, The apparatus is furnished with a positive eye-piece and and is moving in a south-westerly direction. This position a copper plate pierced with circular apertures of various CASES our meridian at about 12 o'clock midnight

diameters, thus forming an adjustable diaphragm. This

copper plate is protected by a disc of asbestos which conFINLAY'S COMET (1906d).- This comet will arrive at its tains a central aperture slightly larger than the largest in perihelion, according to M. Schulhof's elements, the diaphragm. The dark glass is a combination of black September 7.5

mica and blue glass. As shown by the following extract from the ephemeris Using this eye-piece with the full aperture of the Pulkowa published in No. 4109 of the Astronomische Nachrichten, 15-inch refractor, Prof. Ceraski was surprised at the amount the comet is now apparently travelling through the extreme

of detail seen. north-eastern corner of Orion towards Gemini, which it will enter on September 9. On September 7 it will pass about 1° south of 71 Orionis, and on September 13 about 20 go' north of y Geminorum. On the latter date the PHYSICS AT THE BRITISH ASSOCIATION. romet will rise about five hours before sunrise, i.e, about 12.30 a.m.

THE proceedings of the Mathematical and Physical Ephemeris 12h. (Paris M.T.).

Section (A) commenced on Thursday, August 2, with

the delivery of the presidential address by Principal E. H. 1906 a (app.) 8 (app.)

1906
z (app.) 8 (app.) Griffiths, F.R.S. This address has already appeared in

full in these columns (August 9, p. 356).
Sept. 1 5 40
+ 16 37 Sept. 9

+18 27

The chief interest of the meetings in this section 3 5 50 +17 9

6 25
+18 47

arose in connection with several discussions which were s 5 59 +17 39 13

+19 4 arranged and taken up with avidity. On August 2 7 6 8 +18 4

15 6 40 ... + 19 19 the Earl of Berkeley described his experiments on the GREENWICH SUN-SPOT NUMBERS.-An innovation which

measurement
of osmotic pressure, both directly and

The is likely to be found a great convenience by everyone who indirectly from measurements of vapour pressure. has to discuss sun-spot observations appears in the August Mr. w. C. D. Whetham followed, and treated the same

two methods give results agreeing to within 5 per cent. furti ber of the Observatory. Up to the present such workers have had to wait until

subject from the standpoint of thermodynamics and the about the middle of the next year before the serial numbers dissociation theory, thereby stimulating Prof. Armstrong allotted to the sun-spots of any one year by the Greenwich

to make a vigorous attack on everything connected with authorities became available for general use. Now, with thermodynamics and dissociation. În Prof. Armstrong's the sanction of the Astronomer Royal, Mr. Maunder pro

opinion the secret of osmotic pressure is to be sought in poses to publish these numbers month by month.

a thirst of complexes of water molecules. He laid stress The first instalment, giving the numbers for the quarter proved that Boyle's law was satisfied for much greater

on the importance of recent work in America, which January-March, 1906, appears in the current Observatory. Next month's issue will contain the data for the second

strengths of solution than was shown by Lord Berkeley's quarter, and after that each month will be given separately,

results. In the course of discussion it seemed, however, so that the numbers for July will appear in October, and

that the difference was rather one of interpretation of results

than of the experimental results themselves. Mr. Other data, e.g. the duration and the latitude and longi- Whetham, in his rejoinder, declared also in favour of a

thirst tude of each spot-group, are also given, but, as they are

hypothesis, but differed in regard the determined from simply a preliminary examination, these

mechanism of it. are not to be accepted as final values.

On Friday, August 3, two important discussions took

place. The former was opened by Mr. Frederick Soddy, THE ORIGIN OF THE ZODIACAL LIGHT.-Some interesting

the subject being the evolution of the elements. Mr. observational results, and deductions therefrom regarding Soddy outlined the subject from the earliest times to the the origin of the zodiacal light, appear in a brochure

most recent developments in connection with radio-active written by Mr. Maxwell Hall, of Montego Bay, Jamaica, changes. Uranium gradually changes to radium, radium and issued as a reprint from the Monthly Weather Review

to its emanation and several other successive products, until for March, 1906.

in all probability it becomes lead. Lead in turn suffers Mr. Hall's observations were made at Jamaica in 1899

a gradual transmutation into silver. These changes proand 1901, and determined the breadth of the light and its

ceed spontaneously, setting free energy as they occur. boundaries at different distances from the sun.

On re

With regard to active attempts at transmutation in the ducing the observed latitudes according to their longi

reverse direction, which, of course, require a correspondtudes, or distances from the first point of Aries, Mr. Hai | ingly large supply of energy, Mr. Soddy considers that obtained striking evidence which tends to show that the

success will be found first in a nearly complete vacuum light is parallel to the invariable plane of the solar system,

carrying an electric discharge. Here there is very little midence which was apparently confirmed by the results matter carrying a large amount of energy, so that the obtained by other observers.

necessary conditions would seem to be supplied. The On these grounds Mr. Hall arrives at the conclusion

Hon. R. J. Strutt laid stress on the fact that in radiothat the zodiacal light is caused by the reflection of sun- active changes helium was the only non-valent element light from masses of meteoric matter still contained in produced, while in our atmosphere argon was largely prethe invariable plane, which may be considered as

the ponderant. Had argon been formed by other transmutaoriginal plane, of the solar system.

tions? Dr. O. W. Richardson and Dr. H. A. Wilson If this conclusion is correct, and the phenomenon is

discussed the apparent disappearance of matter in vacuum astronomical in its origin, the light should be seen better tubes, alluding to quantitative experiments made in the and more frequently from observing stations situated in

Cavendish Laboratory. Prof. Schuster emphasised the high altitudes, and the editor of the Review especially

nearly complete indifference of radio-activity to temperacommends its observation workers located at such

ture changes, the only temperature effect yet discovered being a small one found by Mr. W. Makower working in

his laboratory. He had experiments in progress on the A Modified FORM OF SOLAR EYE-PIECE.---From Prof. influence of high pressures with the aid of apparatus deCeraski, of Moscow, we have received a brief description signed by Mr. Petavel. With this apparatus a pressure of a solar eye-piece' which he is using, and has found to of 2000 atmospheres can be obtained ; no change in radioBe most effective, for the detailed study of sun-spots. This active charge brought about thereby had yet been detected,

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but the experiments were not yet complete. Prof. S. P. nearly constant rate, but for chords penetrating to a depth Thompson, in reference to the Cavendish experiments, greater than twenty miles the velocity increases to about pointed out that it was well known that gases were 12 kilometres per second, indicating that the wave is absorbed by the walls of vacuum tubes. The Rev. A. L. carried by something more rigid than the outer crust. Cortie, speaking from the astronomical standpoint, was Prof. J. W. Gregory, speaking as a representative of the able to declare that radium had not been detected in extra- Geological Section, considered that Strutt had struck a terrestrial bodies, although helium, which is produced blow at the theory of contraction by cooling. We are no during its decomposition, is discovered in the sun. The longer bound to believe in very high temperatures in the idea of a primitive substance is very ancient; it is simply past history of the earth. Arrhenius's theory may now to the materia prima of Aristotle. A considerable part of dismissed. He suggested the importance of mapping a the discussion turned on the use (or misuse) of the term small area completely in regard to the radio-activity ui atom, a term which Prof. Tilden, speaking as a chemist, the rocks comprised in it. Sir W. Crookes declared his was unwilling to give up. Undoubtedly the term has lost belief that radium inside the earth may not be so radira its original etymological signification, but its use has active as at the surface. Pitchblende in Thick masses become too fixed to expect a change to be readily made. behaves much the same as in thin layers. An experiment The discussion proved so interesting and stimulating that in which 50 mg. of radium were sealed in a glass tuhe Mr. Soddy's paper, which gave rise to it, has been directed and deposited in a cavity in ice, and an exactly similar to be published in full in the report. A more immediate tube containing 50 mg. of silica was similarly deposited, consequence was that the programme for the day was showed that neither sank as much as one-thousandth of completely upset; a large number of papers had to be an inch during prolonged observation. Sir G. Darwin held over in order that the next discussion arranged might directed attention to the work of Gilbeck, Putnam, and be taken. The subject was the notation and use of Hayford, of the United States Coast Survey, who had vectors, and Prof. Olaus Henrici opened it. He fixed a limit of about seventy miles to the thickness of plained the various notations which have been proposed the crust. Sir Wm. Ramsay suggested that Mr. Strutt for vector and scalar products, and proceeded to give should make a special examination of sulphides with the examples of their use. He showed how the operator object of finding whether they contained radium. He might be defined without reference to analytical geometry further queried whether alpha particles give out all their from the relation dU =dp. AU, where U -- any scalar func- energy as heat-a query which must most probably be tion of position, and dp= length of displacement of the answered in the negative. representative point. He then applied the properties of Mr. R. D. Oldham (also representing the Geologica! the operator o to the deduction, with great simplicity and Section) gave distinct evidence, derived from earthquake elegance, of results connected with the theory of partial phenomena, that there must be a central core, the radius differential equations. Dr. C. G. Knott followed, and of which is about 04 of the earth's radius, having raitim deplored the substitution of vectors for quaternions, and less resistance to compression than the main body. Proi objected that neither scalar nor vector product was really H. Lamb threw out a warning against laying too much a true product. He advocated a return to the methods of stress on arguments based on observation of earthquake Sir W. Hamilton. He pointed out that Hamilton does velocities. Too little is known as to effects of pressure and not speak of a vector or a scalar product, but of the vector temperature. of a product and the scalar of a product. With regard to Mr. Soddy showed that another explanation of the the change of the usual negative to the positive sign sug- apparent absence of radium heat might arise from progested by certain vectorists, he explained that it had com- cesses of upbuilding going on which may depend upon ! pelled Gibbs to introduce a third kind of product, and more

possible concentration factor. Prof. Hicks emphasie recently Jahncke had introduced a third in order to be Mr. Soddy's suggestion, and pointed out that able to treat of strains. Prof. W. M. Hicks criticised cooling might be produced by such building-up processes. Henrici's use of brackets to denote vector and scalar pro- He also suggested that the reason temperature does nove ducts on account of liability to confusion. Prof. Henrici, in usually affect radio-active changes is that time comes in an eloquent reply, showed how easily all quaternionic a factor, and he would like to see experimentalls results could be derived from vector analysis.

whether a very long application of a low temperature On Monday, August 6, an important discussion took place would not produce some effect. Mr. Fearnsides indicated on radio-activity and the internal structure of the earth, that in the most radio-active rocks elements of high opened by the Hon. R. J. Strutt. From the examin-atomic weight were associated with those of low atomic ation of a large number of rocks, both igneous and weight. sedimentary, he had come to the conclusion that there is The last organised discussion was held on Tursday, much more radium in all of them than would be needed August 7, the subject being the nature of the radiation to maintain the earth's internal heat if the earth were from gas mantles. Unfortunately Mr. Swinburne, who constituted of rock throughout. Hence he concludes that was to open it, was unavoidably absent; his paper s. the interior of the globe does not contain radium, and therefore read by the recorder. It consisted of a spinird that in all probability its composition is quite different in outline of the various theories that had been proposed to other respects also from that of surface materials. The account for the high luminous efficiency of the Welsbara thickness of the radio-active crust is estimated at forty-five burner, with a declaration in favour of the simple temperze miles at most, which corresponds to an estimated tempera- ture explanation. Low emissivity allows the mantlet ture of 1500° C. at its interior surface. The inside nucleus approach the temperature of the flame: a substance or would be at this temperature throughout just as a loaf of greater emissivity could not rise so high in temperature bread which has been in an oven long enough takes up and consequently the radiation which the latter would a steady temperature equal to that of the oven. In reply give out would not be so rich in luminous qualiina to the possible objection that a gram of radium diffused Though this simple explanation may be ample it dimi through an enormous volume of rock may not develop not follow that there may not be all sorts of rurius nearly so much heat as it would do if concentrated, it was things, such as selective emission, luminescence, ratalois argued (?) that the rate of emission of alpha particles of action, resonance, unstable oxidation and other occurredina pitchblende (to which particles the heat is mainly due) is whose names as impressive as vague." De ! exactly what might be expected on the view that the Rubens, of Charlottenburg, followrd with an accrun ol radium atoms contained in the mineral are as energetic as the experiments which he has recently conducted you they would be if they were all collected together, and (2) which have been described in Drude's Annalen. Ceria 13 direct measurements made by Pegram on uranium and radiations in the immediate infra-red is a very " thorium have shown that these fepbly active elements give radiator, while for luminous and the extreme intrare about the amount of heat which their activity would radiations it behaves much more nearly as a perfet Icad

expect. Prof. J. Milne. who followed, black body. On the whole, the thoria-reria mantis pas directed renewed attention to the bearing on the problem poor emissivity, and its temperature approaches 1600° C.. of the three phases of earthquake tremors. The first, for while the nature of the radiations from the added ceria stations connected by small chords, travels at a slow, confers additional richness on the proportion of lumine

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nature.

rays emitted. An experiment which Dr. Rubens showed disturbed areas of the solar surface and the solar corona; to the section is of great importance in connection with Miss C. O. Stevens, telescopic observations of meteorthe interpretation of the phenomena. Light from an electricological phenomena; the Right Hon. the Earl of Rosse, lantern is focused upon a cold Welsbach mantle, and after the measurement of lunar radiation ; Mr. J. E. Clark, the reflection therefrom is re-focused upon a white screen, A York rainfall and sun-spots; and Dr. W. J. S. Lockyer, blue cell is interposed to isolate the blue portion of the some barometric and rainfall changes of an oscillatory radiation. If now the Welsbach burner be itself lighted so as to heat the mantle, the image on the screen grows In the department of general physics, Mr. C. E. S. fainter: the mantle is a poorer reflector for blue light at Phillips described a glass of low electrical resistivity conhigh than at low temperatures, and it is therefore a better sisting of thirty-two parts of sodium silicate to eight parts radiator wben hot. Indeed, a temperature can be found calcined borax, to which 1.25 parts Powell's flint glass at which it emits as much blue light as a perfectly black is added in order to increase the stability. This glass is body. When the experiment is made with red light the intended to be used for the windows of electrostatic instrureflected light increases with the temperature. Thus the ments which require to be electrically shielded. Its elecfact that a Welsbach mantle is white when cold tells one trical conductivity is about 500 times that of the most nothing as to the character of radiation it will emit when conducting glass hitherto made. When powdered and hot. In the open discussion which followed Prof. S. P. fused on to clean copper, it adheres well without cracking. Thompson considered that Dr. Rubens had demolished | The change of resistivity with heat is being examined. statements made by Mr. Swinburne in a previous paper. In the discussion Mr. Rosenhain mentioned that glasses Prof. Callendar put in a word on behalf of Mr. Swinburne, of the general composition of this one were not unknown in whom he considered to be essentially in the right, though the trade. Dr. Erich Ladenburg gave an account of his he had probably not laid sufficient stress upon the import- researches on nearly pure gaseous ozone. This has a dark ance of the selective character of the radiation of ceria. blue colour in a thickness of 30 cm. In the absorption Dr. Rubens expressed himself also as sharing Mr. Swin- spectrum were discovered five new bands which do not burne's views. Sir Wm. Ramsay directed attention to belong to ozone, but which always appear when the liquid Urbain's recent work on phosphorescence, while the re- ozone is allowed to vaporise. The gas to which they corder of the section emphasised the distinction between belong can be separated from ozone. The change of the opposing schools by pointing out that, according to the volume which occurs when the new gas is transformed " temperature " school, the radiation of the mantle is the and the value of the density indicate that the new gas is sum of the radiations which would be given out by the a more complex form of oxygen. In the discussion Dr. thoria and ceria if separated and still at the same tempera- Rubens, in whose laboratory the research had been conture, while according to the “chemical ” school there is ducted, expressed his belief that it consists of hexatomic present an additional radiation arising from interaction oxygen. Mr. Herbert Stansfield showed a series of photobetween the constituents of the mantle. Dr. Rubens did graphs of thin liquid films in which the two kinds of grey not seem willing to admit that the radiation is wholly of and the three kinds of black are sharply distinguishable this additive type, although it is so in the main. The from one another. A paper by the Rev. B. J. Whiteside discussion was enlivened by the president reading replies was communicated and read by Prof. F. T. Trouton, which Mr. Swinburne had sent ready for use against the subject being the rate of decay of the phosphorthose with whom he had previously engaged in controversy. escence of Balmain's paint. The photometer employed

We will now turn to the papers in connection with depended upon the inverse square law. The standard light which no discussion had been organised.

which was emitted through a small hole could be moved Mr. W. G. Duffield read a paper on photographs of the to various distances from an opalescent screen placed are spectrum of iron under high pressures. The apparatus adjacent to the surface of luminous paint in a box. The by which the pressures were obtained was designed with distance was adjusted so as to maintain the intensity of the help of Mr. Petavel. The photographs which were the two illuminations the same, and the times correspondshown demonstrated clearly that several lines not merely ing to equal shifts of the standard were recorded on widen out, but undergo an actual shift towards the red. a revolving drum. The law of variation of intensity was

Major E. H. Hills and Prof. J. Larmor communi- found to be capable of representation by the formula cated a paper on the irregular motions of the earth's I=1/(a+bt), where t is the time reckoned from that at pole, being a preliminary graphical analysis of their causes. which the paint ceased to be exposed to the exciting light. In the ensuing discussion Mr. R. D. Oldham asserted This result is of great interest, inasmuch as the same law that the amount of matter transferred in a recent Indian arises in connection with the recovery of overstressed marthquake was at least 10,000 times that assumed by bodies, and this correspondence suggests that the mechanism the authors. Prof. Schuster was inclined to question the involved may be similar in the two cases. accuracy of the observations themselves owing to their Sir Wm. Ramsay and Dr. J. F. Spencer described minuteness: the whole shift of axis under discussion experiments on the chemical and electrical changes inamounts only to about 20 feet. Besides, the yielding of duced by ultra-violet light. These were in some the earth owing to the shist of its axis might be the confirmatory of what had previously been done in connecdetermining cause producing the earthquake, and not vice tion with this interesting subject. The result of greatest persa.

novelty and importance is that the fatigue of the surfaces Prol. H. H. Turner read a

a possible effect was found to vary in a peculiar way. The rate of falling of vibration on zenith distance observations, with special off when plotted against the time yields a curve presenting reference to the tremors which threaten the Royal Observ. obvious breaks. In the case of dyad metals there are atory at Greenwich. The special effect referred to is two of these breaks, and two places of constant rate of similar to one observed long ago in Ireland due to the tiring; for tetrad metals four of these stages are observed. L'Ister railway. If the telescope is set and a train passes The paper was read by Dr. Spencer, and Sir Wm. Ramsay the adjustment is found afterwards to be upset. The followed with an extended statement showing how the tremor of the passing train causes a release of any exist- electronic theory of matter accounts for the photoelectric ing strain. Even if at each passage the release of strain effects observed. Dr. O. W. Richardson mentioned that may not produce a visible effect, yet the continued action Dr. Smolochowski in some unpublished experiments had of tremors will be to produce a gradual settling down of succeeded in showing that in a high vacuum the decay the instrument at a different rate from that at which it phenomena cease to take place. would proceed if tremors were absent. In the discussion An important paper was contributed by Mr. F. Soddy the Astronomer Royal for Scotland declared that in his on the positive charge carried by the alpha particle of observatory they were probably free from any tremors, radium C. The substance of this paper has already except those caused by their own lathes. The following appeared in the form of a letter in NATURE for August 2. papers on cosmical physics were also read :--the Astronomer Is or is not the alpha particle charged when it commences Roval for Scotland, spectroscopic observations of solar its separate existence? Mr. Soddy thinks he has proved rclipses: Prof. Schuster and Prof. H. H. Turner, a note that it is not so charged, and, assuming the validity of on rainfall; the Rev. A. L. Cortie, the connection between this conclusion, he considers that possibly too much stress

cases

note on

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