Page images
[merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]
[ocr errors]



UNIFORM WITH This telescope, since its introduction by us three years ago,

“ORIGIN OF Species,” “DESCENT has had a large sale, showing that it has met the requirements

OF MAN," &c. of technical laboratories. Stand only

81 5 0 Stand and good telescope

2 оо Stand and first-class telescope

2 17 6 Rack and pinion, extra

0 10 0 Levelling screws, extra

0 30 Further particulars from THE WEST LONDON SCIENTIFIC With Illustrations. Large Crown 8vo. Two Vols. 58. net.



The Variation of Animals and

Plants Under Domestication.

[blocks in formation]


We learn from the Times that Prof. Adolf Bastian, director and other articles of diet being excluded as channels of of the Berlin Ethnographical Museum, has died at Port of diffusion by the extent of the outbreak and its regular disSpain, Trinidad, in his seventy-ninth year, while on tribution over the whole area. The water supply of Lincoln scientific expedition. Prof. Bastian, who was a distinguished is derived from the River Witham, the water being passed traveller for many years, enjoyed a wide reputation as the through sand filters before distribution. Attention has been author of numerous ethnological and anthropological works, directed from time to time to the unsatisfactory quality of of which the best known is " The Peoples of Eastern Asia." the water, and in 1901 the boring of a deep well into the

sandstone was commenced, but after the bore had reached a The council of the University of Birmingham recently depth of 880 feet in 1903 the boring tool was lost, and has assigned a plot of land on the new university site at Bourn- not been recovered, thus entailing serious delay. The brook in order to enable Mr. Walter E. Collinge, the lecturer epidemic, it is surmised, has been caused by pollution of the in zoology, to continue his experiments and observations Witham or its tributaries above the intake. It is unupon the life-histories of the black-currant gall-mite and

fortunate that works were in progress in the autumn to the plum aphis, with the view of obtaining remedies for improve the filter beds by deepening the layer of fine sand, exterminating or holding in check these pests to fruit

but were put a stop to by the early frost, and the same growers.

event caused many of the consumers to leave their taps The annual dinner of the Institution of Civil Engineers running, and thus to necessitate an increase in the rate of will be held on Wednesday, March 22, at Merchant Taylors' filtration to meet the increased demand. Hall, Threadneedle-street, E.C. Sir Guilford Molesworth, The Fishmongers' Company has published a preliminary president of the institution, will occupy the chair.

report by Dr. Klein, F.R.S., on experiments undertaken for

the company to ascertain the duration of vitality of the An interesting excursion has been arranged by the typhoid bacillus when introduced into shell-fish. The main American Institute of Mining Engineers. In the first conclusions arrived at are :-(1) Oysters readily take up into week in July a meeting will be held at Victoria, British their interior the Bacillus typhosus which has been introduced Columbia, and this will be followed by a three weeks' trip into their shell or into the surrounding sea-water. (2) to the mining districts of Alaska.

Oysters, clean at starting, rapidly clear themselves of the

ingested typhoid bacilli if they are kept in clean water which A VALUABLE contribution to economic geology is afforded

is frequently changed. (3) Oysters, clean at starting, clear by an article on the Hauraki goldfields of New Zealand

themselves of the ingested bacilli to a less extent and slower published by Mr. W. Lindgren in the Engineering and

if they are kept in a " dry "state-i.e. out of the sea-water. Mining Journal of New York. The occurrence of gold is very similar to that in Transylvania. The gold is met with

(4) Oysters, from a polluted locality, clear themselves of the in quartz veins traversing andesite altered into propylite.

ingested bacilli to a less extent, and at a slower rate, even if The minerals accompanying the gold are dolomite, pyrites, (5) Oysters from a polluted locality, containing a large

kept in clean sea-water, than oysters clean at starting. biende, galena, and ruby silver ore. Near the surface the sulphide ores are oxidised ; and the greatest yield of gold

number of the Bacillus coli, very rapidly clear themselves of

This has been obtained at points where the veins cross.

this microbe, whether kept in or out of the water.

shows that Bacillus coli is foreign to the oyster and is In the Transactions of the Faculty of Actuaries, No. 18 rapidly destroyed by it. When, therefore, it is present in the (1905), Dr. James Buchanan discusses the use of various

oyster, it must have been derived from the surrcundings. modifications of Simpson's rule in the performance of the

(6) However largely infected with typhoid bacilli, the oysters integrations involved in the calculation of survivorship

at no time present to the eye any sign of such infection ; benefits.

they remain in all parts of normal aspect. (7) Cockles and

muscles similarly take up the typhoid bacillus, but clear In the Physikalische Zeitschrift for February 1, Pross. themselves much more slowly, particularly in the case of Elster and Geitel discuss the radio-activity of certain sedi- cockles, than do oysters. ments from the German mineral springs, and Messrs. A. Herrmann and F. Pesendorfer describe experiments indi

The geographical results of the National Antarctic Excating traces of radio-activity in the gases from the

pedition, in so far as they relate to the distribution of land, Sprudel spring at Carlsbad.

water, and ice within the area allotted to the expedition for

exploration, were described by Captain R.F. Scott before As interesting feature of the Johns Hopkins L'niversity

the Royal Geographical Society on Monday. He remarked Circular is the series of “ Notes in Mathematics,” edited by

that the main geographical interest of the expedition was Prof. Frank Morley, appearing in the January number.

the practical observation of a coast-line from Mount MelThese notes deal with “ A system of parastroids ” and “ A

bourne, in lat. 743°, to Mount Longstaff, in lat. 83°, and curve of the fifth class ”' (Mr. R. P. Stephens), “ Applications

of the conditions which lie to the east and west of this of quaternions to four dimensions" and “Some invariant

line. The coastal mountains are comparatively low berelations of linear correspondences" (Mr. H. B. Phillips),

tween Mount Melbourne and the Ferrar glacier, and it was 'A closed system of conics " (Mr. Charles C. Grove), and

the tabular structure of these that first indicated the hori.

zontal stratification of the mainland. But low The normal form of a collimation and the reduction of

as the Iwo conies to normal form " (Mr. A. B. Coble).

mountains are, in one place only does the internal ice-sheet

seem to pour any volume of ice into the sea. It is certain Prof. Hans LANDOLT, of Berlin, has received the Prussian that the ice-cap is of very great extent, and there is evidence Imperial Gold Medal for Science.

that it maintains a great and approximately uniform level

over the whole continent. The greater portion of this great The city of Lincoln is now suffering from a serious out- ice-sheet is believed to be afloat. The soundings made by break of typhoid fever. The epidemic started at the begin. I the expedition show that some hundreds of fathoms of water ning of January, and up to date nearly 800 cases have been still intervene between the bottom of the ice at the barrier notified. The epidemic is plainly a water-borne one, milk edge and the floor of the sea; but the barrier edge sixty


years ago was in advance of its present position, in places STEPNEY has published a handbook to the vivaria and as much as 20 or 30 miles, and therefore the soundings lie aquaria in the Borough Museum, the text of which is directly beneath Sir James Ross's barrier, and a considerable reproduced, with certain alterations and additions, from the distance from its edge. The ice-sheet, and the curious and handbook to the Horniman Museum. It is to be hoped often vast ice-formations met with in the Ross sea, are there- that the descriptive portion, when read in the museum, fore regarded, not as the result of present-day conditions, may aid visitors to a right appreciation of the exhibits. but the rapidly wasting remnants of a former age.

but as it stands the guide is admirably calculated to

puzzle beginners in systematic zoology. For instance, Senor A. ARCIMIS informs us that Mr. Valderrama, froin the headings on pp. 24 and 25, the reader would love director of the Municipal Meteorological Observatory at led to infer that while Argyroneta is the scientific desigSanta Cruz (Canaries), observed a fall of dust on January | nation of the water-spider, and Podura aquatica that of the 29 and January 30. During all the former day a very fine water-springtails, Blattidae is the name for the cockroarta dust fell continuously, but not in great amount. On January and from p. 50 that Lacertilia is the generic title for the 30 a rain of a yellow and very fine dust began at 15h. The typical lizards. Again, from p. 17 he would be led to wind-vane pointed to the S.S.W., and the atmosphere was suppose that Gastropoda is the generic term for snails, and charged with the very fine dust, the horizon being invisible that these rank in classificatory value with the viviparous through a kind of dry fog that introduced itself into the pond-snail (Paludina vivipara). Careful study of the text mouth and throat, producing the same effect as when march- may in some cases put matters right, but the muddle is ing on a dusty highway in a hot summer day. All the in- as bad as bad can be for beginners. struments exposed freely out of doors were covered with the nearly impalpable dust.

The address on morphology generally, its modern ten

dencies and progress, and its relation to other sciences, At the recent annual meeting of the Glastonbury Anti- delivered by Prof. A. Giard before the Congress at quarian Society, Prebendary Grant gave an account of the

Sciences and Art at the St. Louis Exhibition in September exploration at the ancient British Lake Village at Glaston

last, is published in the Revue Scientifique of February + bury during the summer of 1904. Three new mounds were

and II.

After referring to the revolution in biology examined, and the exploration of four others

effected, first by Lamarck and subsequently by Darwin completed. The “ finds" included amber and glass beads,

the author proceeds to sketch the gradual evolution of spiral finger-rings of bronze wire, a massive bronze buckle

modern biological conceptions and theories, dwelling espa (taken to have been connected with horse-harness), a bronze cially on Wolff's hypothesis of epigenesis. Reference is object which is supposed to have been some part of horse

then made to the importance of the study of variation, trapping, a variety of bone objects, wool combs, hammers, portion of horses' bits, and a roedeer antler, pointed and

both among living and extinct types, after which the used as a modelling tool for decorating pottery. Several

author passes on to review the influence that palarontology pieces of pottery were dug up. Flint flakes and knives were

has exerted on biology and the doctrine of evolution found, proving that Aint implements were made at the

Abiogenesis next claims attention, while the author nonvillage. With respect to wooden articles, two wheel-spokes,

cludes his discourse by reference to some of the evil: finely turned and finished, were found, and, a fragment of

attendant on the extreme specialisation of scientific work at an axle-box belonging to the

the present day. It is time, he urges, that a general same wheel. Iron bars were found also at the Lake Village, and after minute investiga organisation to direct scientific work should replace the tion the conclusion has been arrived at that these bars are

present state of anarchy, whereby much energy that is now iron currency bars used by the ancient Britons at the time

practically wasted would be diverted towards the attain. of Cæsar's invasion.

ment of a common end and object. A LARGE number of new types of Japanese land-shells of

The fifth part of Mr. J. H. Maiden's "Critical Review the Clausilia group are described by Mr. Pilsbry in the

of the Genus Eucalyptus includes three species. Fouc. December issue of the Proceedings of the Philadelphia lyplus stellulata receives its name from the disposition of Academy.

the buds, and is known as black Sally, or muzzlewood ; the

leaves show longitudinal lateral veins similar to those of the Tue shore fishes of the Galapagos and other Pacific next species, Eucalyptus coriacea, which is distinguished by islands are described by Messrs. Snodgrass and Heller in

its clean white

The third species, Eucalyptus part xvii. of the publications of the Hopkins-Stanford coccifera, confined to Tasmania, is sufficiently hards to Expedition (Proc. Ac. Washington, vi., pp. 333-427). Two

have been planted in parts of the United Kingdom. species are described as new. The Emu for January contains Captain Hutton's presi

The alien problem is not unknown to botanists, and the dential address to the Australasian Ornithologists' Union,

genus Sisymbrium has added two foreign species to the which deals with the geographical origin and subsequent Nora of Lancashire. Sisymbrium pannonicum is definite development of the land birds of New Zealand. An in- naturalised along the coast from St. Anne's to Crosby, and teresting feature of the issue is the reproduction of a photo- according to a recent account by Mr. C. Bailey in vol, sliz graph of a red gum-tree containing the nests of seven part i. of the Memoirs and Proceedings of the Manchesir species of birds.

Literary and Philosophical Society, Sisymbrium stricizes Naturen for January and February contains two illus

mum, a native of continental Europe, has obtained a fros

hold near Heaton Mersey, where it has been observed for trated articles on whales and whaling. In the former issue

fifteen years. Prof. G. Guldberg describes the method of hunting the Greenland right whale, illustrating his article with reproductions In a paper only recently published in vol. ii., No. 3, of the from two old prints. In the February number Mr. E. Contributions from the botanical laboratory of the Chiver Koeford records the capture of a Biscay right whale, or sity of Pennsylvania, but which represents work done (** “nordkaper, at Mjofjord, on the west coast of Iceland, years earlier, Dr. O. P. Phillips maintains that the centrs' and also of a cachalot in northern waters. Two photo- | body in the cells of the Cyanophycea represents a true graphs of the former cetacean are reproduced.

nucleus, but he failed to obtain complete stages in its




mitotic division. Dr. Phillips is of opinion that the FLUORESCENT sutstances are usually regarded as excepmovement of the filaments of Oscillaria and Cylindro- tions to Kirchhoff's law of absorption on account of their spermum is due to protoplasmic processes or cilia which, being able to emit light which in ordinary circumstances he says, are to be observed around all the cells. The they do not absorb, but hitherto no investigation has beeri chromatophore, containing cyanophycin granules, was iden- made of the absorptive power of such substances during tified as a peripheral zone.

active fluorescence. In the Physical Review for December

1904, Messrs. E. L. Nichols and Ernest Merritt show that An interesting address on the present problems of

substances such as fluorescein. when caused to fluoresce meteorology was given by Mr. A. I. Rotch to the section of cosorical physics of the International Congress of Arts

strongly in solution, produce a decidedly different absorpand Sciences at St. Louis, and was printed in Science on

tion from that of the feebly illuminated material, and that the December 23 last. The author pointed out that although it is

absorption curve obtained in this way is intimately con

nected with the curve of fluorescence. In the case of five nearly fifty years since the first commencement of weather

different substances, moreover, there is conclusive evidence telegraphy, and much has been done to complete and extend

of a slight increase in electrical conductivity accompanying the area under observation, the methods employed in the

the phenomenon, and on this account a dissociation hypopreparation of weather forecasts are still essentially em

thesis is brought forward to explain the

of pirical, and practically little or no progress has been

fluorescence. made. This is mostly due to the fact that until recently observations have been carried on solely at the bottom of

An address delivered by Prof. Edward B. Rosa at the the atmosphere. Even the observations made at mountain opening of the John Bell Scott Memorial Laboratory of stations still pertain to the earth and do not represent the Physical Science at Wesleyan University, Connecticut, is conditions prevailing in free air. The still more recent use

printed in Science for February 3. It deals with the of unmanned balloons and kites has led to the acquirement

National Bureau of Standards, which commenced work in of a knowledge of the vertical gradients of meteorological

the United States in 1901, and defines its functions and elements which contradicts previous conceptions, e.g. that

ideals. It is to be noted that research plays a prominent the temperature diminished with increasing altitude more

part in the programme of the bureau. We have already and more slowly, whereas the results show that it decreases

had occasion to refer to Dr. Guthe's critical investigation more and more quickly with increasing altitude. The

of the various forms of silver voltameter (NATURE, vol. lxx., international cloud observations at various altitudes dis

p. 583), and to the determinations by Drs. Waidner and cussed by Dr. Hildebrandsson also show that theories held

Burgess of the temperature of the electric arc (NATURE, heretofore are untenable, and that there is no exchange of

vol. lxxi., p. 132). Both these researches were carried out air between poies and equator. With regard to cosmical

under the auspices of the bureau, and in addition to these, relations to meteorology, the author points out that neither

the Physical Revicw for December, 1904, contains a valuthe effects of the periods of solar or lunar rotation upon

able communication by Drs. Waidner and Burgess the earth's meteorology can be claimed to have been

Radiation Pyrometry," in which the degree of accuracy proved. But coincidences—if nothing more—have been

of several radiation pyrometers is discussed. The bureau shown by Sir Norman and Dr. Lockyer to exist between

does not confine itself entirely to physical and mechanical sun-spot frequency and atmospheric changes, especially as

measurements, but contains


a department devoted manifested by barometric pressure, rainfall, and tempera

chemistry, one of the purposes of which is to attempt to ture. It does not scem impossible, therefore, that the

secure uniformity in technical analyses. A characteristic discussion of meteorological observations from the point of

of the bureau which deserves particular notice is its aim view of their relation to solar phenomena may eventually

not only to conduct investigations through its own staff, lead to seasonal predictions of weather possessing at least

but also to afford facilities for research to others who may the success of those now made daily.

come to work for a limited period as scientific guests. In

this way it is hoped that “the output of original research The Survey Department of the Egyptian Public Works in America will be materially increased.” Ministry has sent us the meteorological report for the year 1902. This volume indicates that the Director-General of covered some years ago by MM. Paul Sabatier and J: B.

Tue remarkable catalytic power of reduced nickel, disthe Survey Department, Captain H. G. Lyons, is making Senderens, has been applied by them in many directions, rapid strides, not only in increasing the number of stations which send in records, but in publishing a considerable

and has been especially fruitful in the addition of hydrogen amount of valuable information which should prove of

to cyclic compounds. Applying this reaction in another

direction, the authors in the current number (February 20) great value. We are told that arrangements are in pro of the Comptes rendus describe the reduction of nitriles to gress for commencing a systematic measurement of rainfall in the Delta and western part of the Mediterranean coast ;

amines. The nitrile, with an excess of hydrogen, is passed that a monthly résumé of the weather has been started; and

over reduced nickel at temperatures between 250° and 300° C. that forecasts during the early and late months of the year anine, but, as

Hydrocyanic acid might be expected to yield methyl

matter of fact, the nickel have been issued. All these show the activity that is being

found to

further action, both dimethylamine displayed in the collection and dissemination of meteorological data. The present report includes magnetic as well

and trimethylamine being produced, together with ammonia as meteorological observations, and also Nile gauge read

and the primary amine. With acetonitrile all three ings. At the end are given numerous curves representing forms about three-fifths of the mixture, predominating.

amines are likewise produced, the diethylamine, which the variations of the meteorological elements as registered Dipropylamine was similarly the chief product of the at the Abbassia Observatory,

reaction with propionitrile; with capronitrile, derived from The Journal of the Röntgen Society (vol. i., No. 2) con- ordinary amyl alcohol, besides the three amines, two of tains a note by Mr. J. H. Gardiner on the new ultra- which were new, an appreciable proportion of the hydroviolet glase manufactured by Messrs. Schott and Genossen, carbon a-methyl-pentane was obtained. The yields were in of Jena ; it is illustrated by photographs of spectra showing all cases good with fatty compounds, but the reaction was the transparency of the glass in the ultra-violet region. less satisfactory when applied to the aromatic series, there





March 5.




12h. 34m.

being a tendency for the hydrocarbon and ammonia to be detail in an illustrated article by Prof. Barnard published the chief products,

in No. 1., vol. xxi., of the Istrophysical Journal.

The telescope was erected, at the cost of Miss Catharin Globus for February 23 is a special number containing Bruce, at Yerkes in April

, 1904. but has now been tits contributions by friends and admirers of Prof. R. Andree, mounted and shipped to Mount Wilson, Pasadena, where who reached his seventieth birthday on February 26.

it is to be used for photographing those regions of the

Milky Way not attainable at the former observaton. The third part of the British Journal of Psychology, pub

It consists of a 3-inch guiding telescope firmly bolted to

two other tubes, which carry photographic doublets of lished by the Cambridge University Press, has been 10-inches and 61-inches aperture respectively. The fecal received. The number contains five papers in addition to length of the 10-inch is only 50 inches, and the poiar a report of the proceedings of the Psychological Society. axis of the instrument has been formed by bending the Mr. Norman Smith discusses Malebranche's theory of the upper part of the iron pier to the required inclination perception of distance and magnitude; Mr. F. N. Hales

that the camera may make a complete revolution about the

axis without having to be “ reversed.' For use in different considers the materials for the psychogenetic theory of

latitudes an iron wedge-shaped section may be introduced comparison ; Mr. W. G. Smith makes a comparison of between the upper and lower parts of the pier in order some mental and physical tests in their application to to produce the required change of indination, whilst a epileptic and to normal subjects; Prof. Mary W. Calkins special arrangement, whereby the clock motion may be redefines the limits of genetic and of comparative psychology, driving gear so that the same mounting may be used in

versed in two minutes, has been introduced into the and Mr. C. Spearman makes an analysis of " localisation, illustrated by a Brown-Séquard case.

the southern hemisphere.

The 10-inch doublet, by Brashear, gives excellent defin tion over

a field zo wide, and the scale is such that 1 inch=1°:14, or 1° = 0.88 inch. The ratio aperture 'lical

length=1/ 5.03 is that which Prof. Barnard believes to OUR ASTRONOMICAL COLUMN.

be the best for the purpose for which this instrument was ASTRONOMICAL OCCURRENCES IN MARCH:

designed. The 64-inch Voigtländer doublet has a focal

length of 31 inches, and is used in conjunction with the 17h. Sun eclipsed ; invisible at Greenwich. 10-inch for the purpose of verification. Specimen photo7. 13h. Juno in conjunction with Moon. Juno graphs accompany the description, and these instify 1° 27' S.

eloquently to the satisfactory performance of each of the 9. Jupiter in conjunction with Venus. Venus 5° 30' S. doublets.

ih. Jupiter in conjunction with Moon. Jupiter
3° 15' N.

Physical CONDITIONS OF THE PLANETS.- In a communicajoh. im. to ih. 6m. Moon occults Tauri

tion to No. 3992 of the Astronomische Nachrichten Prof. (mag. 3'9).

T. J. J. See deals exhaustively with the methods that he has Minimum of Algol (B Persei).

employed and the results he has obtained in a research 00 20. gh. 2m. to gh. 49m.

Moon occults B. Virginis the internal densities; pressures and moments of inertia of (mag. 3:8).

the principal bodies in the planetary system. Some of the 9h. 23m. Minimum of Algol (B Persei).

results obtained in the preliminary discussion of the avail12h. Venus at maximum brilliancy.

able fundamental data are of great interest. For example, 24. 7h. Mars in conjunction with Moon. Mars 3° 40' S.

he arrives at the conclusion that the most probable values Vesta in opposition to Sun.

for the rotation period and for the oblateness of Uranus

are roh. 6m. 40.32s. and 1: 25 respectively, whilst for Nep REPORTED DISCOVERY OF A SEVENTH SATELLITE TO JUPITER.

tune the similar values are probably 12h. som. 535. and --A telegram received from the Kiel Centralstelle announces 1:45 the discovery of a seventh satellite in the Jovian system. In the case of the earth, Laplace's law of densities The description reads :-16 magnitude, position on February appears to be a natural law, for the value obtained for the 25 62 degrees, distance 21 minutes, daily motion 60 seconds

oblateness of the outer stratum, or surface, of the globe south-easterly.

agrees very well with that obtained as a mean of the most

trustworthy of the determinations by more direct methods PLANETARY TIDES IN THE SOLAR ATMOSPHERE.-In a com- The probable value obtained for the pressure acting at the munication published in the Bulletin de la Société astro- earth's centre is 2383.152km. of mercury, a quantity so nomique de France (February, 1905), M. Émile Anceaux enormous that Prof. See attempts to render it more discusses the question as to whether the undecennial prehensible by suggesting that it is 7838 times as great periodicity of sun-spots may not result from the fluctuations

as a column of mercury equal in height to the Eiffel Tower. of tides set up in the solar atmosphere by the concerted The probable pressure at the sun's centre is nearly 212 action of Jupiter, the earth, Venus, and Mercury. He billion atmospheres. A column of mercury acting solely classifies the tides as binary, ternary, and quaternary, under terrestrial gravitational acceleration would have to according to the number of planets acting in their produc- be high enough to extend beyond the sun in order that it tion by being in, or near, opposition or conjunction. The mighť exert such a pressure. ternary tide due to the combined action of Jupiter, Venus, Similar results for the density and pressure at different and the earth is supposed to be the most important factor levels in the planets and satellites are given in two of in regulating the appearance of spots, and a curve showing the tables accompanying Prof. See's paper, and are also the fluctuations in the strength of this tide, as calculated shown diagrammatically, whilst a third table shows the from the knowledge of the planetary positions, agrees ratios of the actual moments of inertia to those of rorrefairly well with the sun-spot curve for the years 1891 to sponding homogeneous spheres. 1905.

Finally, the author arrives at a number of conclusions of DISCUSSION OF CENTRAL EUROPEAN LONGITI DES.-In which the more important are :- (a) That sun-spots are

series of tables published in Nos. 3993-4 of the Astritiomisch! the indirect consequences of such tides; (b) that the com

Nachrichten, Prof. Th. Albrecht brings together, weighs bined action of the three planets especially mentioned

and tabulates all the longitude results, affecting central governs the fluctuations of the spot period ; (c) that this European observatories, hitherto obtained. In the first ternary tide obeys an eleven-year period ; (d) that the

table the longitude differences between 176 pairs of observ. variation of the sun-spot period is due to the eccentricities ing stations, as determined since 1863. are thus dealt with of the planets, chiefly Jupiter.

whilst in the second the longitude differences between

Greenwich transit circle and numerous other important The BRUCE PHOTOGRAPHIC TELESCOPE.-The Bruce photo-circles or observatories are brought together. In the third graphic telescope, with which a number of beautiful photo- table the corrections to be applied to the differences given graphs of nebulæ, Milky Way regions, &c., have already in table i., as determined from the discussion of the whole been obtained at the Yerkes Observatory, is described in set, are shown.



« PreviousContinue »