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HE study of marine life by the sea-side is not only 3

TH April 26

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delightful occupation in itsell, but is now considered 27 8 15 24 +43 38.8

as an almost essential part of the training of every young +44 143

biologist. It is also one of the most fruitful fields al 29 8 27 13 +44 473

inquiry for the elucidation of the fundamental problems 8 33 11 30 +45 17-5 9'9247

0.61 of biology. Several marine stations have now been Brightness at time of discovery=1.0.

erected on our coasts, in which a naturalist may gain a An observation by Dr. Palisa at Vienna on April 8 gave practical knowledge of the rich fauna and fora of the a correction of +2s. and +0:2.

sea, and where he may apply those modern and often CHANGES ON Mars.-A telegram from Mr. Lowell, pub- expensive methods of experiment and research which can lished in No. 4010 of the Astronomische Nachrichten,

only be carried out in a well equipped laboratory. announces that colour changes similar to those previously

Among the most successful of these institutions is that reported are again taking place in some of the Martian

of the Liverpool Marine Biology Committee, established features. The Mare Erythræum, just above Syrtis, has again

first on Puffin Island in 1887, and subsequently moved to changed from a blue-green to a chocolate-brown colour.

its present quarters at Port Erin. It is chiefly due, we This change was first observed by Mr. Lampland on April 4,

believe, to the efforts and enthusiasm of Prof. W. H. and the Martian season now corresponds to our February.

Herdman that this laboratory was founded. To help the In a communication to No. 4, vol. xiii., of Popular student to make good use of its resources, Prof. Herdman Astronomy, Prof. W. H. Pickering observes that ice will

is now editing a series of small practical monographs

known the L.M.B.C. Memoirs. Much valuable probably begin to form at both poles of Mars during the

time may be wasted, many serious errors may be compresent month, the north pole being turned towards the earth at an angle of 10°-13° This opposition is particu- mitted, and many precious opportunities may be lost in larly favourable for observations of the green colour over

the practical study of marine biology through the want a greater part of the planet's surface, as Mars will be

of proper guidance, or through the ignorance of the more favourably situated than during the preceding or the

literature of the subject. Well stocked libraries are rarely following opposition. Its apparent diameter will be from

to be found near at hand, and, moreover, it often happens 13" to 17", and the poles should appear either of a pure

that the commonest animals and plants are just those white, a light yellow, or a vivid green colour, the first

which have been least completely described in readily

accessible works. named being due to hoar-frost or snow, the second to

It is with a view to remedy these clouds, and the last named, in part at least, to vegetation.

defects that the memoirs are being published. As the PHOTOGRAPHY

editor tells us in his preface, the series deals with those PLANETARY NEBULÆ.-In No. 356

types which have hitherto not been adequately described in of the Observatory Mr. W. S. Franks suggests that special attention should be paid to the photography of

English text-books and laboratory manuals.

Some thirty volumes are promised. They range over planetary nebulæ by those observatories which possess almost the whole of marine life-from the diatom to the long-focus cameras. Whilst using the late Dr. Roberts's sea-weed, from the sponge to the porpoise. Twelve volumes 98-inch “ Starfield ” reflector, Mr. Franks attempted to

have already appeared. These are :-(1) Ascidia, by the photograph these interesting objects both with and with

editor ; (2) Cardium, by J. Johnstone ; (3) Echinus, by out a secondary magnifier, but in the first case the images H. C. Chadwick ; (4) Codium, by R. J. H. Gibson and obtained were indistinguishable from those of the surround

Helen Auld ; (5) Alcyonium, by S. J. Hickson ; (6) Leproing stars, whilst in the latter the definition was very un

phtheirus and Lernæa, by Andrew Scott; (7) Lineus, by satisfactory. One point which is strongly in favour of anyone enter

R. C. Punnett; (8) Pleuronectes, by F. C. Cole and J. Johning this field of research is the fact that the light emitted by J.'R'A. Davis and H. J. Fleure; (11) Arenicola, by

stone ; (9) Chondrus, by O. V. Darbishire ; (10) Patella, by these objects is of a highly actinic character necessi

J. H. Ashworth ; (12) Gammarus, by M, Cussans. Not tating only short exposures.

only is a detailed and accurate account given of the strucRADIAL VELOCITIES OF “STANDARD-VELOCITY STARS."- ture of each type, but its habits, life-history, and embry. No. 3, vol. i., of the Mitteilungen of the Nicholas Observ- ology are also dealt with, and its "economic" asperts atory, Pulkowa, contains a number of results obtained by

are not forgotten. Prof. Belopolsky for the values of the radial velocities of On the whole, the various monographs seem to us the standard-velocity” stars. Each of the values was

most trustworthy, and reflect great credit on the work of obtained from the measurement of about fifteen iron lines the authors, who, indeed, are for the most part specialists on a single plate, and the date, time, and hour-angle is thoroughly familiar with the types they describe. Yet it given in each case. The stars dealt with in the present must be confessed that the volumes differ considerably in publication

Arietis, Persei, Pegasi, and merit and attractiveness. Some of them contain Title B Geminorum, and taking the mean of the several values that is either new or original. Among the most interek given in each case the following respective velocities are ing of those already published we may mention the este obtained = -12.30 km. – 2.14 km., +5.72 km. (one lent volume on the plaice, Pleuronectes, by Messrs. Cole plate) and +4.21 km.

and Johnstone, which has already been reviewed in Naturs, MAGNITUDE EQUATION IN THE Right AscENSIONS OF THE also the memoir on Arenicola by Mr. Ashworth. Berth Eros STARS.-In Bulletin No. 72 of the Lick Observatory these seem to us models of what such monographs should Prof. R. H. Tucker discusses the magnitude equation be-clear and practical descriptions of the anatomy and which enters into the observations of the right ascensions life-history of the animals concerned, with some discussing of the Eros stars as observed at various stations engaged of the general problems suggested, and good illustrations. in the work. Comparing the equations in the first and Naturally enough the embryology is in most cases Very second Eros lists, it is found that there is no marked briefly described, and often the accounts provided : similarity between the two sets observed at the same chiefly derived from the works of other authors. station ; different instruments, and probably in some cases question, indeed, whether it is really worth while repro different observers, having been employed. At Lick the ducing in such monographs figures illustrating the de effect of magnitude has been measured by screen observ- velopment which can be found in almost any text-book ations at three different epochs for the same observer and While both a table of contents at the beginning. art instrument. For clock stars the correction obtained was an index at the end, may not always be necessary, yes 0 007 second per magnitude, and, assuming it to vary with it is a pity that many of the monographs should be put declination, this would give 0.010 second and 0.008 second lished with neither. In some cases, also, the figures are per magnitude for the first and second lists respectively. scarcely clear enough; but considering the very moderate Confirmation of this, in general, is found in the Königs-price at which they are issued, the L.M.B.C. Jemoirs an berg results obtained with a clock-driven micrometer in excellently printed and illustrated. They will double which it is assumed that the magnitude equation is fully justify the hope of the editor, and will prore mar eliminated. Other tables given show the variation of the useful to students of marine biology, who will await with error with varying magnitudes.

eagerness the appearance of the remaining volumes.




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and the altitude of the central reach became more VICTORIA FALLS."

aggerated as time passed. Including the height of the

falls (400 feet), this difference is now about 1000 feet. WHEN Dr. Livingstone discovered the Victoria Falls in Of the process by which the river cut back this Grand

1855, he sought to explain their origin by calling Cañon and shaped the falls as they are seen to-day, the in volcanic agency, and stated that they were simply caused by a crack made in the hard basaltic rock from the right to the left bank of

PLAN OF the Zambezi, and then prolonged from the left bank away through 30

VICTORIA FALLS . or 40 miles of hills." All subsequent

by travellers support the same idea ; but in his article Mr. Molyneux, in

A.J.C.Molyneux F.G.S. the Geographical Journal, claims

Scale of Feet that, as at Niagara, the combination of cañon, gorge, chasm, and falls is

Nat.Scalel: 25,000 or 2.53 Inches - 1 Mile due to erosion and the constant reducing action of the Zambezi River (Fig. 1).

In explaining his theory, the author first refers to present-day conditions of the river, and divides it into three portions; the coastal, stretching 360 miles up as far as the Kebrabasa Range-a portion of the mountain axis of South Africathrough which it runs in a gorge


Z 35 to 40 miles in length. The

Landing Stage middle reach is 600 miles long, in low-lying country, and is divided from the upper regions of the river by the high Victoria Falls, 1000 miles from the coast.

The geology of the country around the falls is then sketched briefly.

R During what was probably the Tertiary period, South Central Africa was subject to vigorous yolcanic action, the concrete forms of which can now be seen in the denuded and exposed lava-flows of the Limpopo and Zambezi valleys. In the vicinity of the falls, the Batoka Stony wooded

Rocky country, the basalt is interbedded

"Bars with the soft forest sandstones, but

slope to water the Zambezi River, in draining the ancient lake regions of Central Africa, has eaten into the overlying sediments until it has reached the


Byrka 1. hard and almost level igneous sheet

Main Island Rainbow

Fall in which the falls occur. This sheet extends from the end of the cañon,

ThèC has 40 miles east of the falls, to beyond

343 14

Eastern the Gonye Falls, 120 miles northwest.


Poirt On reaching the top of this sheet, the erosive action of the river was

Railway Bridge checked; but conditions were favourable in the middle regions of Rouge

Bojong Pot the river, which had no protective

storu covering, and where the rocks are

country unresisting sandstones and Coalmeasures. A difference of level between the two regions came into existence-defined by the eastern edge or fringe of the basalt sheet.

It may be understood that the eastern edge would be thin, and the backward erosion of the Zambezi

Rough stony from its middle reaches would

country quickly break into it. But as the

Zambézi River. thickness of the basalt increased as

Gorgead to extend the river receded westwards, the cutting action became slower, until the rate of deepening of the middle reach and Kebrabasa gorge far out

Fig. 1.- Plan of Victoria Falls. From the Geographical Journal. stripped the slower process of forming the Grand Cañon of the Victoria Falls. The difference | author states that, as is common to all rocks of this between the river bed where running on the basalt sheet nature, it is full of cracks and fissures due to contraction,

| Abstract of a paper by Mr. A. J. C. Molyneux in the Geographical generally assuming a columnar form. These columns can Jonurnal for January.

be seen at low water along the lip of the falls, more or

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less truncated as the verge is reached, and bearing little evidence of attrition (Fig. 2). Mr. Molyneux is of opinion that the cutting back of the falls is due to the perpetual hammering action of the vast bodies of water falling into, and down upon, the cracks between the basalt columns, assisted by the constant vibration of the rock from the precipitated masses of water, and that by this constantly exerted force the columns are rent asunder and fall into the chasm, taking with them huge and deep flakes of the precipice. At low water heaps of these blocks, as yet angular and unreduced, may be seen in the shallower ends of the chasm.

Such is one phase of the erosion of the falls. Another power is at work below the water line. The blocks that

water, such parts as are protected by islands must be free from such erosion. To-day there are three important islands on the lip of the chasm, and more than fourteen large ones in 4 miles of river above the falls. In the channels between, there must be more prolonged submission to moving currents, by which the cataracts at the ends of the chasm are being deepened into sloping by-washes.

The falls have checked the deepening of the Upper Zambezi, and until they chisel the groove of the Grand Cañon back to the western edge of the basalt sheet, the upper reaches must continue to run at a high altitude and amid low-lying hills. This has prevented the Zambezi becoming a navigable river throughout, and has also bad a marked influence on the geography of South Africa.


Proto. by Pedrotti, Bulawayo. Fig. 2.- View of Victoria Falls seen through the jaws of the Gorge. Danger Point on the left; the promontory of the "knife edge" on the right.

From the Geographical Journal.


fall into the chasm disappear in the deeper waters at the jaws of the gorge—yet, impelled by the rush of the current in the confined walls, they must be grinding down and perpetually deepening the cañon, to emerge at the eastern end as rounded pebbles and form the shingle beds of the middle reaches.

The extraordinary zig-zags acute angles in the cañon have always aroused comment, and the author thinks that two main causes are responsible for themthe position of islands that probably studded the river (as now) and also the existence of master joints and fissures in the basalt. On Boaruka Island this action is exemplified in a striking manner, for a stream can be seen falling down a crevice, that forms, peculiarly enough, another acute angle with the chasm. Granted that the falls are due to the action of moving

SEISMOLOGICAL NOTES. THE attraction of the moon has always been felt by

earthquake workers, whatever may be its effect on earthquakes themselves. The latest contributions to this aspect of seismology are two papers in No. 18 of the Publications of the Earthquake Investigation Committee in Japan. Prof. Omori deals with the lunar daily distribution, finding maxima of frequency between oh, and 5h., and again between 12h. and 13h., reckoning from the upper culmination. Dr. Imamura, dealing with the synodic monthly variation in frequency, finds that this shows an increase at the syzygies and quadratures; the former is attributed to the combined effects of the attrac tion of the sun and the moon, while the latter is explained by the fact that the time of high water at Tokio then coincides with that of the diurnal maximum of barometric




pressure. In spite of the ingenuity of this explanation, its At this stage it is extremely sensitive to the light convalidity seems doubtful, for the stresses involved can at ditions of its environment, assuming the colour of its most be only a subsidiary cause of earthquakes, and con- surroundings within twenty-four hours. If the environsequently any effect due to them would naturally be looked ment be changed, sympathetic change of colour takes place for at the time when they vary most rapidly in amount in three days. Half- and full-grown Hippolyte are less rather than at that of their maximum.

susceptible. With them sympathetic colour-change occupies The same publication contains a paper, of some im- a week or more. portance in this connection, on daily periodic changes of level in artesian wells, by K. Honda. It is the account

March 30.-" On the Distribution of Velocity in of a record, obtained by a self-registering instrument, of

Viscous Fluid over the Cross-section of a Pipe, and on the the daily changes in level of two artesian wells, 380 metres

Action at the Critical Velocity." By J. Morrow. Comand 300 metres depth, in Tokio and Yokohama. Each

municated by Prof. H. S. Hele-Shaw, F.R.S. of them showed a periodic change of level which is

Summary and Conclusion.-(1) The experiments provide directly correlated with the tides in the neighbouring sea, velocity distribution, but show that this distribution can

a partial confirmation of the theoretically obtained law of and also a variation due to changes in barometric pressure, of such amount as to show that one-third of the changes only be obtained under very special conditions, of which

absolute freedom from obstructions and end effects are in the first case, and one-fourth in the second, are absorbed by the rocks overlying the water-bearing stratum.

important; and hence (2) When the flow is direct and

stream-lines exist, the velocity distribution is not necessarily The catalogue of earthquakes felt in Austria during the

exactly that which may be described as characteristic of year 1903. forming No. 26 of the Mitteilungen of the Austrian Earthquake Commission, is the last of the series

“normal” flow. (3) At the critical velocity the irrotawhich will be published under the auspices of the Academy

tional straight line motion ceases and is followed by one

in which the paths of the particles of fluid are eddying of Sciences. In the introduction to the catalogue it is

and turbulent. The law of distribution of mean linear announced that from the beginning of 1904 the task of collecting and publishing the records of all earthquakes,

velocity parallel to the axis simultaneously changes from · whether of local or distant origin, observed in Austria, was

the parabolic (or approximately parabolic) to that typical taken over by the Zentralanstalt für Meteorologie und

of eddying motion. (4) The critical velocity in question Geodynamik. The Earthquake Commission, having pub

(being that at which eddying motion ceases to be trans

formed into direct motion, and not that at which a highly Jished the earthquake registers up to the end of 1903, will in future confine itself to the encouragement and publi- accompanied by a sudden change in the velocity parallel

unstable stream-line motion is suddenly disturbed) is not cation of purely scientific investigations.

to the axis at any point in the cross-section. On the After the collapse of the campanile of St. Mark's, in

other hand, as the total Aux increases, the experiments 1902, there was a popular demand, inspired by the idea that the detonation was likely to precipitate the destruc

show a gradual transition from one state to the other,

due to the change which has occurred in the law of tion of other historic buildings in Venice, for the cessation

velocity distribution. (5) The observations have little bearof the usual mid-day gun. The idea was, of course, un

ing on the upper limit of stream-line flow, as observed founded, but to allay the alarm Prof. Vicentini was re

by colour bands. They indicate, however, that the unquested to instal one of his microseismographs, and his

stable direct motion would follow an approximately parareport has now been published. The instrument

bolic law of velocity distribution (as represented by the attached to the wall of the ducal palace which faces the

equation obtained for stream-line motion), and that at the lagoon and is directly exposed to the sound waves of the higher critical velocity this distribution would suddenly cannon; it indicated a vertical displacement, in conse

change to that represented by the equation given for eddyquence of the report, of 0.012 mm. to 0.014 mm., and

ing motion. In this case, then, instead of a gradual á horizontal displacement of 0.007 mm. to 0.012 mm., being change of velocity, there would actually be sudden and about one-half of those produced by a person jumping on large changes in the velocity parallel to the axis at different the floor of the room in which the instrument was in

points in the cross-section of the pipe. (6) The “ Pitot stalled, and one-fifteenth of the displacement caused by

law (v=v2gh) is at least approximately true at exa high wind. From these figures it is evident that the

ceedingly low velocities. sound waves of a cannon can have no appreciable effect on a building, though plaster may be detached where this April 6.-" The Influence of Cobra-venom on the Proteid has become loosened and separated from the wall by an Metabolism. By Dr. J. Scott. Communicated by Sir air space.

Thomas R. Fraser, F.R.S.

Conclusions.-(1) Practically no change in rate of proteid

metabolism was induced by the administration of cobraSOCIETIES AND ACADEMIES.

venom, in spite of well marked local reaction. (2) A slight

decrease in the proportion of urea nitrogen, quite insignifiLONDON.

cant compared with that produced by diphtheria toxin and Royal Society, February 23. — “The Colour-physiology of various drugs, was observed. (3) A slight rise in the prothe Higher Crustacea," Part iii. By F. Keeble and Dr. portion of ammonia nitrogen occurred. (4) There was a F. W. Gamble. Communicated by Prof. Sydney J. Hick- slight rise in the proportion of nitrogen in purin bodies. son, F.R.S.

(5) The nitrogen in other compounds showed no constant (1) The chromatophores of Hippolyte and Crangon are change. (6) The P,0, excreted showed no constant change, multicellular structures. Their branches show differenti- but in two experiments there was a slight rise. The change ation into a firmer ectoplasm and a more fluid mobile produced in the proteid metabolism is, therefore, small, endoplasm in which the pigment occurs. (2) The form- and such as it is, being in the directions of decreased ation of the pigments in the larval and post-larval chro- elaboration of urea and increase in the proportion of matophores is described. (3) In addition to pigments, fat, nitrogen excreted as ammonia, it seems to indicate a slight in the form of colourless globules, occurs in the chromato- toxic action on the hepatic metabolism rather than a phores of Hippolyte. This fat lies in special cells of the

general action on the proteid changes, and tends to conchromatophore, and exhibits a mobility similar to that of firm the view that the poison acts chiefly upon the nervous the pigments of the chromatophore. (4) If fed and kept system. in the dark, or if starved and kept in the light, Hippolyte loses little of its chromatophoric fat. Depletion of fat

Entomological Society, April 5.-Mr. F. Merrifield, occurs, however, in starved, dark-kept animals. These, president, in the chair.--Specimens of a melanic Grammowhen exposed to sunlight for five or six hours, show fat ptera, discovered by Mr. J. C. T. Poole at Enfield, and in their chromatophores. These results show that the apparently quite distinct from any member of the genus colourless chromatophoric fat is a reserve food material,

taken in Britain : H. St. J. Donisthorpe. Mr. Gahan, and point to the conclusion that in the accumulation of to whom the species had been referred, considered it to this reserve fat light plays an important part. (5) At the be a form of G. ruficornis.-A specimen of Megalopus tinie of settling on the weeds of the sea-shore, Hippolyte melipoma, Bates, an insect which so much resembles a varians is a colourless or faintly brown-striped animal. bee that Bates had said they were indistinguishable in


nature : M. Jacoby.--Specimens of Papilio macleayana when determining the horizontal component of the earth's and Hypocysta metirius captured in Queensland, illus- magnetic field by the ordinary method is the moment of trating the use of " directive ” markings in the Rhopalo- inertia of the magnet which is used in the vibration excera in influencing their enemies to attack non-vital parts : periment. It is usual to determine the moment of inertia A. Bacot.-An example of Ceratopterus stahli, Wast., a of the cylindrical brass bar supplied with each instrument beetle from Australia possessing notable powers of crepi- by calculation, then by measuring the period of the magnet tation : G. J. Arrow.-A series of Erebia alecto (glacialis), alone, and when loaded with this bar to calculate the var. nicholli, Obth., taken at about 8000 feet at Cam- moment of inertia of the magnet. This method pre piglio, South Tyrol, with specimens of Dasydia tenebraria, supposes that the density of the inertia-bar is uniform var. wockearia, caught in the company of the Erebias in throughout. It is not easy to secure a bar of which the the same localities; when upon the wing the two species density is uniform throughout, and further it is difficult

not dissimilar: A. H. Jones and H. Rowland- to test whether such uniformity has been secured. The Brown. Mr. Jones also exhibited examples of Erebia author thinks that more trustworthy and uniform results melas from the Parnassus Mountains, Greece, for com- would be obtained by determining once for all, with very parison, and fine forms of butterflies found at Mendel, near great care, the moment of inertia of a standard bar and Botzen.-A series of Morpho adonis from British Guiana, then determining the moment of inertia of the bars supwith the very rare dimorphic black and white female : W.J. | plied with the different magnetometers, by comparing Kaye.--The social web and pupal shells of Eucheira them with the standard bar experimentally. In the paper socialis, Westw., together with specimens of the perfect is described an instrument suitable for comparing the insect, being the actual nest from Mexico described and moment of inertia of bars, together with some experiments figured by Westwood in the Transactions for 1836: Dr. made with a view to determine the moment of inertia of F. A. Dixey. After Dr. Dixey had read a note upon the a standard bar, and an investigation of the influence of the habits of this and similar species, the Rev. W. T. Holland, air upon the period.--Exhibition of a series of lecture exof Pittsburg, Pa., U.S.A., gave his personal experiences periments illustrating the properties of the gaseous ions of social silk-cocoon spinning species also from Mexico. produced by radium and other sources : Dr. W. Watson. -A note recently received from Mr. S. A. Neave giving further interesting evidence of the superstitious dread of Royal Astronomical Society, April 14 -Mr. W. 11. Naw, larvæ with terrifying eye-like markings entertained by president, in the chair.-Spherical aberration of object South African natives : Prof. E. B. Poulton.-Experi- glasses : A. E. Conrady. The paper dealt with the differ ments to ascertain the vitality of pupæ subjected to sub- ence of phase at the focus caused by the spherical aberta mersion : F. Merrifield.-Pseudacraea poggei and Limnas tion. Two different rigorous solutions, by which such chrysippus ; the numerical proportion of mimic to model :

differences could be conveniently computed, were deduced H. A. Byatt.—A monograph on the genus Ogyris : G. and discussed. The paper also dealt with the relation Bethune-Baker.

between these differences of phase and spherical aberration

in the geometrical sense.-(1) A suggested arrangement Geological Society, April 5.-Dr. J. E. Marr. F.R.S.

for the mounting of a cælostat ; (2) point distributions no

a sphere, with remarks on the determination of the apps president, in the chair.-On the divisions and correlation of the upper portion of the Coal-measures, with special spectrograph attached to the Newall telescope of the Cam

of the sun's motion : H. C. Plummer.-The four-prist reference to their development in the midland counties of England: R. Kidston. The following classification of

bridge Observatory, with remarks on the general desiga

of spectrographs for equatorials of large aperture, cum the Coal-measures is proposed by the author :

sidered from the point of view of "* tremor-discs"; H. E.

Newall. Proposed names

Names previously used (4) Radstockian Series Upper Coal-measures.

Royal Meteorological Society, April 19.- Mr. Richard (3) Staffordian Series Transition Series. (2) Westphalian Series = Middle Coal-measures.

Bentley, president, in the chair.-An account of the obsery

ations at Crinan in 1904, and description of a new meteor(1) Lanarkian Series = Lower Coal-measures (including the Millstone Grit). ations, which are carried out under the direction of 3

ograph for use with kites : W. H. Dines. These obsery.

joint committee of the Royal Meteorological Society ani --On the age and relations of the phosphatic chalk of of the British Association, are made with meteorographs Taplow: H. J. 0. White and L. Treacher. The rocks attached to kites with the object of ascertaining the rorat the locality of Taplow are described in detail, and the ditions prevailing in the upper atmosphere. During last following classification is adopted :-(E) Upper White summer the kites were flown from the deck of H.M.S. Chalk (visible), 16 feet; (D) Upper Brown Chalk, or rich Seahorse, which was placed at the disposal of the coonphosphatic band, about 8 feet; (C) Middle White Chalk,

mittee by the Admiralty, Mr. Dines designed a new and about 16 feet ; (B) Lower Brown Chalk, or rich phosphatic inexpensive meteorograph, which he now fully described band, about 4 feet; (A) Lower White Chalk (visible), The weather conditions of last summer were somewhat 17 feet. Fossil-lists are given from each of the above unusual, there being a decided preponderance of east und divisions, and the authors conclude that the Lower White south-east winds. Near the summit of Ben Nevis the air Chalk belongs to the zone of Micraster cor-anguinum, and was often dry, and was on several occasions warmer than the succeeding beds to that of Marsupites testudinarius ; the air at the same level at Crinan. As a rule, hower, while the lower phosphate-band represents the lower part the temperature on Ben Nevis is generally much lerne of the Uintacrinus-band, and the upper one that of the than the temperature in the free air at the same level. Marsupites-band of that zone.

On several occasions temperature inversions were observed

at levels between 3000 feet and 7000 feet. A fact previous! Physical Society, April 14.-Dr. R. T. Glazebrook, F.R.S., noticed was again observed, viz. the decrease of strength past-president, in the chair.-Ellipsoidal lenses : R. J. of easterly winds with elevation.-Rate of fall of rain » Sowter. The paper extends the treatment of thin Seathwaite : Dr. H. R. Mill. This is a discussion of the ellipsoidal or astigmatic lenses, and gives a simple solution records from a Negretti and Zambra self-recording rsim for complex problems of the following types :-" To deter- gauge during a period of eighteen months. Scathwaite, mine the astigmatic pencil, after refraction of an astig- which is in Borrowdale, Cumberland, is in almost matic pencil by an ellipsoidal lens.” And “to find the wettest spot of the British Isles, the average yearly rainfa ellipsoidal lens equivalent to two cylindrical lenses placed being about 137 inches. Dr. Mill's results seem to see a definite distance apart, with their axes inclined at any that the rainfall at Seathwaite in an average year indicates angle."

The method of treatment can be applied to a tendency to be greater during the hours of darkness than crossed ellipsoidal lenses, in contact, or separated, and is in daylight, that rather less than half the time during applicable in general to astigmatic pencils.--Determination which rain is falling it continues without intermission de of the moment of inertia of the magnets used in the at least six hours at a time, and that rather more thom

half the total amount of rain is deposited in such long field : Dr. W." Watson. One of the constants required showers.

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