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condition of the planet, and, being caused by snow, corroborate the theory of an atmosphere, without which snow could not be produced. Early in the season, when not so well situated for observation as now, the snow cap at his south pole was a conspicuous object, but as that has melted under the summer sun, only the dark, somber planet may now be seen. When his winter is prolonged one will appear at the north pole.

Jupiter. Dr. Edward E. Barnard, of Lick Observatory, has devoted much time to the determination of the equatorial and polar diameters of Jupiter, as observed with the 36-inch refractor, using uniformly a magnifying power of 520. The mean results of all his measures are as follow: Equatorial diameter, 38.532′′ ± 0.024=90,190 miles; polar diameter, 36・112′′ ± 0.032-84,570 miles. This, which he thinks is very near their true value, differs from other observations by an entire second, or over 2,000 miles, and leads him to the conclusion that the determination of the true size of Jupiter is not an easy problem.

In relation to the spots that often suddenly appear on Jupiter's disk, Prof. G. W. Hough, of the Evanston (Ill.) Observatory, says: "They appear in a medium, having a depth of some thousands of miles, and also have a freedom of motion in this medium. This points to the conclusion that the planet is gaseous, which is borne out by the gradual fading of the light of the satellites when projected on the disk of the planet."

Jupiter's Fifth Satellite.-Dr. Barnard, the discoverer, by a prolonged series of observations, determined the values of its eastern elongations during 1893-'94, and finds the mean value to be 47.785" ±0.044", corresponding to a distance from Jupiter of 111,910 miles, or about 67,000 niles from the surface. He finds, however, the elongation a varying quantity. No observations could be obtained of its western elongations. The sidereal period of revolution, from a mean of all the observations, he deduces as 11h 57m 22-618° ±0.013, in an eccentric orbit. M. Tisserand finds that the major axis of the orbit must make a complete revolution in the astonishingly short period of five mont... The motion of this satellite about its primary is 16.4 miles a second, making it the most rapidly revolving satellite known-even twelve times swifter than the rate of Phobos, the inner satellite of Mars. From several considerations he has been led to believe that it can not exceed one hundred miles in diameter, and may be less. If it were greatly over one hundred miles, its shadow on the planet could be seen with the 36-inch telescope.

Diameter of Saturn. -The exact determination of a planet's diameter, owing to obstacles of an optical character, is a difficult problem. "The secondary spectrum of the refractor," says Prof. Wermann Struve, "causes want of definition of the boundaries of the planet's disk; this effect is increased by diffraction and by unsteadiness of the air. In addition to these and other difficulties, the micrometer employed seems to influence the result." A series of results from 1826 to 1887 shows in the case of Saturn an uncertainty of at least a half second, the best heliometric observations giving its equatorial diameter as 17.1", and the axis of the ring as

39.5", while best filar micrometer measures give, respectively, 17.7" and 40-3". A series of 93 measurements made with the 30-inch Pulkowa refractor, from 1889 to 1892 inclusive, for the determination of the orbits of Rhea and Titan, gives 17-471" for the equatorial diameter of Saturn, and 39-2" for its ring. Similar uncertainties obtain with the other planets.

Variables. The director of Harvard College Observatory, Prof. E. C. Pickering, in his annual report, says that in a photograph of the cluster Omega Centauri, Prof. Bailey counted on a region the size of the sun 7,000 stars, two of which have been found to be variables. In "Astronomische Nachrichten," Prof. Pickering announces that Mrs. Fleming has discovered four new variables, one, a star in Sculptor, right ascension Oh 10.4m; declination 32° 36', varying from 6.5 to 10th magnitude in 366 days. Another is in Scorpio, right ascension 16h 50-3m; declination south, 30° 26', varying from 73 to 11-6 in 278 days. The third is in Ophiuchus, right ascension 17h 14.5m; declination north 1° 37', varying in 348.4 days from 8.5 to 12.5 in magnitude, and the fourth was found in Aquilla, right ascension 19h 46.5m; declination north 4° 13', varying from 9.5 to 12th magnitude in about a year.

Dr. S. C. Chandler discovered on Aug. 5 a remarkable variable star of short period, which has received the name Z. Herculis. The following synopsis will show the rapidity of its fluctuations, as observed in Leyden: On Sept. 18, 1894 -at 7h 45m, magnitude 487; at 8h 7m, magnitude 3-91; at 8h 45m, magnitude 3.58; at 9h 41m, magnitude 5.25; at 10h 12m, magnitude 6-38; at 11h 5m, magnitude 7.92. On Sept. 20-at 7h 54m, magnitude 8.09; at 9h 34m, magnitude, 8-26. On Sept. 22-at 7h 17m, magnitude, 6; at 8h 44m. magnitude 3.25; at 10h, magnitude 6.33. On Sept. 24-at 7h 24m, magnitude 8-09; at 8h 30m, magnitude 8:59. This star, which is of the Algol type, is Durchmusterung + 15° 3311; right ascension (1855) 17 51m 34s; declination + 15° 9-3′.

Temporary Stars. - The history of astronomy includes about a dozen well-authenticated instances of the appearance of new stars, and it is a curious fact that the last two, the one in Auriga and that in Normæ, should have manifested themselves within two years of each other, and that the earliest record of their existence should in both cases have been made by photography. These stars, like all of this character, appeared suddenly. Stars of this kind were formerly supposed to be very rarely seen, but this number shows them to be not so unfamiliar. Examination of their spectra showed that each prominent bright line in the Nova Auriga had a corresponding bright line in Nova Normæ, and that every hydrogen bright line had a companion dark line by its side in both spectra, the dark line in every instance being toward the violet end of the spectrum. The Nova Normæ was discovered on Oct. 26, 1893, by Mrs. Fleming, of Harvard College Observatory, during the inspection of a photograph taken on July 10, 1893, at the observatory founded by Harvard at Arequipa, Peru. The spectrum of this new star is declared by Prof. Campbell to be unmistakably nebulous. The behavior of Nova Auriga has been unique, the cause of which is not apparent. That its brightness has exhibited strange fluctuations is admitted by all, but that it has assumed the character of a nebula is disputed. At Lick Observatory it presented to Dr. Barnard the appearance of a small bright nebula consisting of a nucleus surrounded by a pretty bright but dense nebulosity 3" in diameter. On the contrary, Mr. Newall, observing with a 25inch refractor, found the Nova to be truly stellar. At Pulkowa it was seen as a nebula. At Upper Tulse Hill, with an 18-inch refractor, it appeared as truly stellar as a star near it. Prof. Vogel has suggested that a possible explanation of the nebulous appearance observed at Lick, Pulkowa, and other observatories, may be found in the chromatic corrections of the telescopes there employed, the greater part of their light having been near wave length 5,000, if the telescopes had been focused on a neighboring star. Prof. Campbell has compared the spectrum, both ↑ visual and photographic, with those of 5 nebulæ, and regards 19 lines thereof, including the lines of hydrogen, which are common alike to Lebulæ and stars, as probably identical with lines in the spectra of the nebulæ.

Elements of Alpha Centauri. The orbit of this double star-our nearest stellar neighbor -which has hitherto been held as uncertain, the estimated periods ranging from seventy-seven to

| eighty-eight years, is now among the best determined of the known double star. Dr. See finds from the parallax of Gill and Elkin (0.75") that the semimajor axis of the orbit is 23-592 astronomical units; so that the companion moves in an orbit that is about a mean between those of the planets Uranus and Neptune, but the eccentricity is so great that in periastron the distance (113) but little surpasses that of Saturn, while in apastron it considerably exceeds the distance of Neptune from the sun, becoming 36 astronomical units. He makes the time of periastron A. D. 1876-62; period, 81-07 years; eccentricity, 0-52; length of major axis, 32.5"; length of minor axis, 6-16"; distance of star from center. 5-94".

Bright-Line Stellar Spectra.-Prof. Campbell has observed that the 9.3 magnitude star, Durchmusterung + 30 3639, is surrounded by an extensive hydrogen envelope. The star is of the Wolf-Ragot type, and its spectrum is very rich in bright lines, about 30 having been observed between wave lengths 656 and 426. Visually, *he most striking features are the continuous spectrum, the bright line at wave length 5,694, the bright-blue band at wave length 4.652, and the very bright hydrogen H. B line. This latter line, when observed with a narrow slit, is a long streak extending a very appreciable distance on either side of the continuous spectrum, but seen with an open slit it is a large circular sk about 5" in diameter. This appearance has Dot been observed in the spectra of any other stars of this type.

No. 3200 of the "Astronomische Nachrichten" eontains a catalogue of 99 stars of remarkable spectra, by Rev. T. E. Espin, of Wolsingham Otservatory, Darlington, England. His opinion is that the more banded the spectrum the peater is the difference between the visual and the photometric magnitude. Of T Corona be says: "The nebular spectrum has entirely

disappeared. The region from declination north 51° to 56°, bounded by 10h 40m to 11h 8m in right ascension, is remarkable for the number of strongly colored stars. Out of 108 stars, as counted on the charts, 17 are orange red, showing plainly a grouping of tinted stars in this part of the heavens."

Comets. The years 1893-'94 were unusually barren of cometary apparitions, but three having been seen, and two of these-Tempel's and Encke's were expected. The former, Tempel's (periodic) comet II of July 3, 1873, with a period of about five and a quarter years, was observed by Mr. Finlay, of the Cape of Good Hope Observatory, on the night of May 8, 1873. Its brightness scarcely equaled that of a star of the eleventh magnitude. It was seen at its next apparition in 1878, but escaped detection in 1883 and in 1889.

Comet a 1894 was discovered by Denning, of England, on the evening of March 26. It had a daily motion of about 1o in a southeasterly direction. It was at all times very faint. The following elliptical elements for this comet are by

J. R. Hind:

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The comet announced as having been discovered by Edwin Holmes, of London, England, on April 9, proves on investigation to have been a nebula, No. 6503 of Dreyer's New General Catalogue of Nebulæ.

Comet b 1894 (Gale). This comet, detected on April 1, became visible to the naked eye on the 7th of that month, and on the 25th had attained to the fourth inagnitude. The tail, though not at any time visible to the naked eye, was on the 12th 2° in length and 1o broad, but on the 15th had entirely disappeared. The diameter of the coma was 12', which was constantly maintained. Dr. Kreutz has computed for it the subjoined elements:

Epoch, 1894. April 18-5576, Berlin mean time.
Node to perihelion
Longitude of node
Inclination.

Log. of perihelion distance...........

824° 17′57-8" 206°21′13-5" 87° 3′80-6 9-992746

On the photographic negative plates of the total solar eclipse of April 16, 1893, appears a nebulous object which can not be other than a comet. It is present on 12 of Prof. Schaeberle's plates from Guiana, on 3 Harvard College Observatory plates, on 2 British plates taken in Brazil, and on 3 British plates in Africa. Study of these negatives shows that the object had a progressive motion, and that unquestionably it was a comet and ought to receive the designation of comet I, 1893, which cognomen Dr. Krueger has given it.

Encke's comet was discovered on Nov. 1, 1894, by Cerulli, of Italy.

Comet V 1889 (Brooks). - A thorough discussion of this comet has recently been made by Mr. C. Lane Poor, with a view of determining or disproving its identity with the celebrated Lexel's comet of 1770. He finds that comet Brooks, though originally moving in an orbit of

long period, on approaching the planet Jupiter was diverted and not only changed in orbit, but became entangled in his satellites for 2.65 days, during which time the comet made a complete revolution around Jupiter, passing over an are of 313° of longitude. Previous to this approach to the great disturbing planet, he ascribes to comet Brooks a period of 31-38 years, with an uncertainty of 12 year. The tendency of the research is to disprove the identity of this comet with that of Lexel, though the latter passed also between Jupiter and his satellites; but the matter has been much discussed, and the suspected identity will probably never be either substantiated or disproved.

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Spectrum of Comet b 1894 (Gale).-With a narrow slit, Prof. Campbell saw a bright line at wave length 563, terminating the yellow band; another at 474, terminating the blue band; and two bright lines in the green band were measured at wave lengths 5,163.5 and 5,124. His conclusion was that the four lines were the edges of carbon bands at wave lengths 5,635, 4,737, 5,165-3, and 5,129, which in every respect seemed to agree with the observations of Prof. Vogel. The spectrum was photographed on several nights, with long exposures. On one evening 6 bright lines were recorded; another, 15 bright lines and the unresolved band at wave length 47 were depicted, and, later, with greatly extended exposure, 22 bright lines were photographed. Comparison of this spectrum with that of comet b 1893 shows the two to be identical. The conclusion arrived at is that the principal lines are due to the presence in both comets of carbon and cyanogen, but the origin of several of the fainter lines is unknown. The spectrum of comets more nearly resembles that of a burning compound of carbon than one of carbon made incandescent by electricity.

Jupiter's Family of Comets. - Nearly all, if not every one, of the comets of short period were made thus by the perturbing influence of Jupiter, and hence their paternity is ascribed to him. In their journey to the sun they traveled near the giant planet, whose superior attraction changed their orbits from ellipses of long period, or perchance parabolas, to ellipses of short period. The appended list is his family record so far as known. Nearly all have been observed at more than one apparition: Lexel's of 1770, De Vico's, D'Arrest's, Finlay's, Denning's I. Denning's II, Faye's, Tempel's I, Tempel's II, Swift's I, Swift's II, Barnard's I, Barnard's II, Brooks's I, Brooks's II, Encke's, Spitaler's, Brorsen's, Wolf's, Holmes's, Winnecke's, Tuttle's, Biela's (lost).

There are a few others having short computed periods, but too much uncertainty attaches to them to warrant their introduction into this table.

Asteroids. This year there has been a lull in the discovery of these little planets, and but few new members have been added to the aster oid group. In March, 1893, as many, less one, were found as have been discovered in the past eleven months. But astronomy is the gainer by the infrequency of their detection. The following list comprises all those to be added to the catalogue incorporated in the last volume:

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So far as known, not one of these has received a name, nor have any names been given, save a few, to those found in 1891-'93. The entire number of these bodies is a little uncertain, but will not vary much from 388.

Diameters of Asteroids. - As is well known, measurement of the diameters of the asteroids

has been deemed impossible, but Dr. Barnard thinks the brightest of them easily measurable with the 36-inch telescope of the Lick Observatory. "Astronomy and Astro-Physics" for May, 1894, contains a history of the determination by several astronomers of the diameters of Ceres, Pallas, and Vesta, but the results are very discordant. All measurements hitherto have given the largest diameter to Vesta; but Dr. Barnard, with the great telescope, using a power of 1,000, has made micrometrical measures of Ceres, Pallas, and Vesta, and has found the diameter of Ceres twice as large as either of the others. Subjoined are his filar-micrometer measures of these three planetoids:

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Meteors. While information has been had from various parts of the world of about the usual number of bolides, yet, as usual, the accounts are so at variance that it is difficult to obtain data of sufficient exactness for computation of reliable orbits. A gratifying exception is the report of a meteor of this sort seen at and in the vicinity of Grahamstown, Cape of Good Hope, on the evening of April 6, 1894, which is thus described by Mr. L. A. Eddie, F. R. A. S.: "When first seen it was about 6° above the western horizon, moving very slowly to the east, having in its wake a brilliant train some 30° in length and 2 or 3° in width, much resembling a bright comet with a long tail. When nearing the eastern horizon the flame was extinguished and it resumed the appearance of a glowing ball of molten matter, as it had on its first apparition in the west. It was visible for thirty seconds. The cause of its slow motion was, doubtless, its direction of motion, that having been from west to east, the same as that of the earth." Headds: "I had never before seen a fire ball rise

and set as this one did. There was no accompanying noise or appearance of an explosion during visibility. It was seen at various places in the colony, and all agree that no noise was heard or explosion seen."

A majority of fire balls move in the same direction as the earth, or from west to east, and, as the motion of both is about the sun, such meteors overtake the earth. On the contrary, those having a retrograde motion are themselves overtaken by the earth. Results derived from observation of 321 of the largest fire balls seen during the past thirty years show 59-2 per cent. of the former class and 40.8 per cent. of the

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Constant of Aberration.- Mr. Preston, of the United States Coast Survey, having discussed the observations made at Waikiki, Hawaiian Islands, finds it necessary to make a correction to the generally accepted value of the constant of aberration from 20.445" to 20-433′′ ± 0.034. This value, combined with the latest determinations of the velocity of light (186,333 miles) and Clark's value of the earth's radius (3,963-3 miles), gives the sun's distance and equatorial horizontal parallax as follow: Distance, 92,700,000 miles; parallax. 8-82".

Change in the Astronomical Day. In answer to the question asked of astronomers in all countries by the Physical Society of Toronto, whether it be desirable that the astronomical day should begin at midnight instead of at noon, 179 replies were received-107 in favor of and adverse to the proposed change. Of the opPosition most were Germans. The time indiated for the inauguration of this change of the day's beginning is the first day of the twentieth century, Jan. 1, 1901.

Universal-time Movement. Considerable progress has been made, both during the past and the present year, by the project for the adoption by the Eastern Continent of a zonal system of time similar to that which for several Years has been in use in the United States and Canada, Germany has adopted mid-European time, one hour fast of Greenwich, and made it the legal time of the German Empire. The same system obtains in Italy, Denmark, and Switzerland. England, Belgium, and Holland eGreenwich time. Japan and Australia are Line hours fast of Greenwich time. The United States and Canada are four, five, six, seven, and eight hours slow of Greenwich time, and the differences are named colonial, eastern, central, mountain, and Pacific time, respectivehy. When the standard time was changed in Fly the twenty-four hour system of reckoning Was introduced also, O hour being midnight. Astrographic Charts.-Work on these charts Lay now be regarded as fairly begun. Up to

the beginning of the present year reports were received from 7 of the associated observatories that the plates secured amounted to 1,731, the total number assigned to them being 8,308. If the unreported observatories are equally advanced there should be no difficulty in completing the catalogue plates before the year 1900. Of chart plates, however, only 415 have been taken by the same 7 observatories, so that the date of completion of the long-exposure negatives, even without duplication, is still very uncertain. Letters from the directors of several observatories engaged in the work testify to the practical difficulties encountered by them, notably with the Réseaux, the films of which seem liable to perish, causing faults in the photographs.

Celestial Photography. -The application of photography to astronomical purposes is rapidly extending, and is arousing a spirit of emulation not confined to the great observatories, nor to eminent specialists like Roberts and Barnard, and is achieving valuable results.

MM. Loewy and Puiseux, of the Paris Observatory, at a recent meeting of the Paris Academy of Sciences, exhibited some photographs of the moon, taken with the equatorial coudee, which were larger than those taken at Lick Observatory, and bore enlarging well. One of the enlargements represented the moon on a scale nearly six feet in diameter, rare, indeed, because the atmosphere will seldom allow the taking of a photograph of which such enlargement is possible.

Photographic Nebulæ. Suspecting that there was a nebulous region hitherto unknown in the vicinity of the Pleiades, not reckoning the nebulæ of the cluster itself, Dr. Barnard subjected that portion of the sky to an exposure of 10h 15m, and secured a number of singular curved and streaky nebulosities apparently connected with the Pleiades, and extending all about the group. Some of these streams stretch out irregularly several degrees on either side of the cluster.

North of the Pleiades, from right ascension 3h 20m to over 4h, and from declination + 30° to several degrees farther north, is a district singularly devoid of small stars, but filled with large masses of exceedingly diffused nebulosity, never before known or imagined. Differing from all other nebulous clusters, the nebulosity of the Pleiades is condensed about the individual stars.

In December, 1892, and January, 1893, the entire constellation of Cassiopeia was photographed by Dr. Max Wolf, which revealed the structure of the Milky Way. Also numerous nebulæ were recorded on the plates (with exposures of fifteen and sixteen hours), which were to a large extent connected one with another by faint nebulous bands and streamers. He mentions as a typical form of these nebulæ that of a funnel narrowing to a curved tube or pipe, which ends in a chain or series of stars.

Publications. - Prof. S. W. Burnham, in a quarto volume of 255 pages, Vol. II, "Annals of Lick Observatory," has recorded his own work on double stars-the result of his studies with

the 36-inch and 12-inch refractors of that institution. He gives full details of micrometrical measurements of between 800 and 900 objects. In discussing his measures of the celebrated trapezium of Orion, or Theta Orionis, he enters into an elaborate examination of the alleged discoveries with small telescopes of stars in and about the trapezium, and gives a diagram of all that have been seen by the 36-inch telescope, amounting to only 3, besides the 6 wellknown ones forming the trapezium. In the progress of his study of the double stars he has discovered 9 new nebulæ, has taken measures of 28 planetary nebulæ, and has made observations of the physical structure of 38 other nebule. The importance attaching to the micrometrical measurements of the planetary nebulæ arises from the fact that almost every one has a star in its exact center. The precise place of a nebula which has within it no visible star can not be accurately determined. Though, doubtless, all are in motion, yet no movement has ever been determined in any nebula, or any variation in brightness.

"Monthly Notices" of the Royal Astronomical Society of England, for June, 1894, contains 2 maps drawn from Dreyer's New General Catalogue of nebulæ and clusters, made on an equalsurface projection, showing their general distribution in both the northern and the southern heavens. The resolvable nebulæ are marked with red dots, the irresolvable with black, and the clusters are indicated by a cross. The author is Sidney Watters.

Another valuable record may be found in No. 325 of the "Astronomical Journal," which is wholly occupied by Dr. Barnard, of Lick Observatory, with accounts of the micrometrical measurements, by the 36-inch glass, of the fifth satellite of Jupiter and of the planet Jupiter itself. He, the discoverer of the new satellite, looks with disfavor on the numerous propositions by astronomers to confer upon this little new-found moon a mythological name, and his wish is that it be known simply as the fifth satellite of Jupiter. These are the results of his measures of the planet: Equatorial diameter, 90,190±56 miles; polar diameter, 84,570±75 miles; polar compression, 698.

Dr. Barnard finally adopts as the period of the new satellite 11h 57m 22-6185 ± 0.0138.

Cordoba Durchmusterung.-Vol. XVI of the publications of the Observatorio Nacional Argentino contains the first installment of an immense and most important work. It is a continuance from the southern limit-in reality overlapping it by one degree of the celebrated astronomers Argelander and Schonfield of their Durchmusterung, and records the positions and magnitudes of all the stars to the tenth magnitude inclusive, from south declination 22° to 32°.

Vol. XVII continues the Durchmusterung from declination south 32° to 42°. In the two volumes are comprised the positions and magnitudes of 340,380 stars from the first to the tenth magnitudes. The area covered is 6,075 square degrees of a great circle. It shows an average density of 56-2 stars to a square degree. In the Milky Way the density occasionally reached to 160 stars. For the preparation of both catalogues 1,108,600 observations were required. This herculean work was performed between 1885 and 1891 by Prof. John M. Thome, director of the Cordoba Observatory, Argentine Republic, and is comprised in 12 charts, 20 by 26 inches in

size, containing the places of 340,380 stars of the proper magnitudes, and positions for the epoch 1875-0.

Chandler's Second Catalogue of Variable Stars. All who take an interest in stars of this kind will welcome the appearance of this list. Its arrangement is very complete in respect to place, color, limits of range, period, epoch, and terms of inequality, while interesting particulars are added in footnotes. It is considered a valuable acquisition to the literature of variable stars.

In Nos. 3233 and 3234 of the Astronomische Nachrichten, double-star observers will find a catalogue of 187 double stars observed by Prof. G. W. Hough with the 184-inch refractor of Evanston, Ill., and a series of measures of 182 known pairs.

Vol. III, "Annals of Lick Observatory," follows quickly the appearance of Vol. II. It contains 4 monographs of different subjects, the most valuable of the series being by Prof. James E. Keeler, now director of Allegheny Observatory, but formerly of the Lick Observatory staff. The treatise relates to his spectroscopic observations of nebulæ with the appliances on Mount Hamilton. He establishes beyond controversy that the principal nebular line has no connection whatever with the magnesium fluting. His determination of the wave length of the nebular line is 5,007-05±03 tenth metres, and that of the magnesium fluting 4,959-02 ± 04 tenth metres. It follows, therefore, that neither of these lines coincides with that of any known terrestrial element. The third nebular line is the H β. one of the hydrogen lines. The motion of a nebula to or from the earth may be determined by the displacement of the hydrogen line. In this manner Dr. Keeler ascertained that the famous Orion nebula is traveling away from the sun, or that the sun and solar system are leaving the nebula, at the rate of about 11 miles a second. Also that, on the other hand, Struve VI-a planetary nebula, right ascension 18h 7, declination north 6° 50′-is moving toward us apparently 6.5 miles a second.

Prizes. The Arago medal, of the value of 1,000 francs, was awarded to Dr. E. E. Barnard by the French Academy of Sciences on Dec. 18, 1893, for the discovery of the fifth satellite of Jupiter. It was at the same time conferred upon Prof. Asaph Hall, in recognition of his finding of the two moons of Mars in 1877. Only one other has received it-Leverier, for his discovery of Neptune.

The gold medal of the Royal Astronomical Society of England has been received by Prof. S. W. Burnham, of the University of Chicago, for his discoveries and micrometrical measures of double stars, and for his researches on the orbital motions of binary systems. The number of double stars discovered by him is about 1,300. The Lalande prize was bestowed upon M. Schulhof for cometary work.

The Valz prize fell to Herr Berberich for work on the asteroids, and the Janssen gold medal was awarded to Prof. Langley, for astronomical physics.

The Donohoe comet prize bronze medal has been forwarded to Mr. Gale for the discovery of comet b 1894. This medal was awarded to Mr.

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