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Barnard's comet 1884 II, which has not been seen at the last two returns, if we except an uncertain observation by Swift in 1895, should be at perihelion in October. Its position will be about as favorable as in 1895, and perhaps a little better, so that there is a possibility of its being found.

No ephemeris of any of these objects is yet at hand.

Brorsen's comet, which has been lost since 1879, should be at perihelion about the close of this year and in fairly good position for observation. The fact, however, that it was not found at the equally favorable opposition of 1890, leads astronomers to think that something has happene to change the course of this comet. Dr. J. R. Hind and Dr. E. Lamp in Astronomische Nachrichten, Vol. 137, p. 110, point out that possibly Denning's comet 1894 I may have been a fragment of Brorson's comet, the two objects having been in nearly the same position in space in February and March, 1881. Denning's comet is due at perihelion in June, 1901.

METEORS.

After the failure of the great Leonid shower to materialize in November last it may be rash to make any more predictions concerning it, but there are several indications that the prediction of last year was a year, possibly two years, early, and that we may look for fine showers in 1900 and 1951. The observations seem to indicate that the maximum of the shower this past year occurred on the morning of Nov. 15, instead of Nov. 16 as redicted by Messrs. Johustone and Stoney, so that probably the maximum next November will be on the date predicted by Mr. Denning (See PoULAR ASTRONOMY No. 69, Nov. 1899, p. 479). The Andromede or Biclid shower occurred in 1899 on the night of Nov. 24, and will probably not be noticcable in 1900.

The following table of the radiant points of the more prominent meteoric showers by Mr. W F. Deuning is abstracted from "the Companion to the Observatory" for 1900.

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The Perscids, with a maximum on August 10, are visible for a considerable period and the radiant exhibits an easterly motion among the stars, changing from R. A. 202, Decl. + 51°, July 19, to R. A. 53°, Decl + 58°, Aug. 16.

Ephemeris of Eros.-The following ephemeris of Eros has been computed with the elements given by Henry Norris Russell in A. J. 457.

EPHEMERIS FOR GREENWICH MIDNIGHT.

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In Science of Dec. 1 and Dec. 8 abstracts are published of the papers, about a third of them spectrose ›pie, presented last summer at the first meeting of the Astronomical and Astrophysical Society of America.

The relative photographic brightness of Mars and Jupiter has been measured by Dr. J. Hartmann at Potsdam (Berlin Sitzungsberichte, July 20, 1899; Astrophysical Journal, Nov.) Using a new type of photometer he finds that for the light of greatest photographic activity (λ 4760 to λ 4110) the surface brightness of Jupiter is almost exactly identical with the surface brightness of Mars, while the surface brightness of the brightest-southwest-portion of the Moon is about one fourth that of either planet. The distance of Jupiter from the Sun was a little less than 3.5 that of Mars; the intensity of illumination,

varying as the square of the distance inversely, was consequently for Mars 11.9 that for Jupiter. In order that the surface brightness should be the same for the two planets the reflecting power, or albedo, of Jupiter must for the part of the spectrum under consideration be 11.9 that of Mars. The visual albedo of Jupiter Professor Müller has found to be 2.8 that of Mars, as against Dr. Hartmann's ratio of 11.9 for the violet albedo, while Professor Lohse has found Jupiter's photographic albedo, where the ultra-violet is effective in addition to the violet, to be 18 8 that of Mars. Evidently the violet of Mars is relatively weak, and the ultra-violet very weak; as might be expected from the planet's pronounced reddish color.

In the Astrophysical Journal for November Mr. Harrer of the Allegheny Observatory gives the results of his examination of the spectrum of a Orionis during the star's irregular minimum at the past opposition. Comparing his spectrograms of this period with Professor Keeler's spectrograms of 1894 he has detected no change in the number or relative intensities of the lines in the green and yellow of the spectrum.

The American Academy of Arts and Sciences have appropriated the sum of $500 to assist in the construction of a large spectroscope to be used at the Yerkes Observatory by Professor Frost for the determination of motion of stars in the line of sight.

In the choice of officers of the British Astronomical Association Mr. J. Evershed was reelected for the current year director of the section of spectroscopy.

A summary is given in Science of Dec. 8 of the results of Dr. Chase's careful investigation of the refraction of red stars. While the excess of red light in these stars might be expected by its smaller refrangibility to diminish the amount of their general refraction, Dr. Chase agrees with previous observers in finding that the refraction for the red stars is the same as for the other stars.

In the Astrophysical Journal for November Professor Campbell reports that he finds variable motion in the line of sight for ẞ Capricorni and v Sagittarii.

In the forthcoming 'Revised Harvard Photometry' a column is promised giving, for each star whose magnitude has been determined, the character of its spectrum; and also, where possible, the photographic magnitude will be given, by comparing which with the visual magnitude the star's color may be determined.

Dr. Wilsing, continuing his investigation of the effect of pressure on spectra, has obtained (Astrophysical Journal, November,) by moistening carbon electrodes with water, results for hydrogen analogous to his previous results for other ele

ments.

Professor Hale has recently confirmed and extended his observations of carbon in the Sun's chromosphere (Yerkes Observatory Bulletin No. 12; Astrophysical Journal, November,). The green fluting of carbon, terminating at A 5165 was found in the chromosphere as long ago as September, 1897, the identification of the feeble bright lines of the fluting in the chromosphere being accomplished by

first putting the slit of the spectroscope on the Sun's disc and then moving quickly to the Sun's edge, when the dark carbon lines were replaced by bright lines. In Aug. 1899 with the reconstructed spectroscope this green fluting was observed better than before, a large number of bright lines being visible. With perfect conditions and adjustments the yellow fluting, terminating at a 5635, was seen. The blue fluting, which terminates at a 4737, could not be seen.

VARIABLE STARS.

J. A. PARKHURST.

Minima of the Variable Stars of the Algol Type.
(Given to the nearest hour in Greenwich Time.)

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The above ephemeris was computed from the elements given in Chandler's Third Catalogue with three exceptions. For U Cephei, Chandler's revised elements given in No. 396 of the Astronomical Journal; for DM. + 12°3557, Luizet's elements given in No. 3596 of the Astronomische Nachrichten; for DM. + 45°3062, Pickering's elements given in Harvard College Observatory Circular, No. 44. The long period variables must still await the appearance of an ephemeris in the Vierteljahrsschrit or the Companion to the Observatory.

ANDERSON'S NEW VARIABLE IN HERCULES.-This is the first of the new variables noted on page 537 of the December number. The place there given is

R. A. 17h 53m 27.7*

55 24.7

Decl. 19° 29′ 41′′, (1855)
29 20 (1900)

The place was also measured by Dr. Hartwig with the 7-inch heliometer of the Remies Observatory in Bamberg, Germany. He gives as his results in No. 3603 of the Nachrichten

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The accompanying charts will aid in finding the field, which is 1° south of the 4.5 magnitude star 95 Herculis. The first chart, on the scale of the DM, gives the stars from the 6th to the 9 5 magnitude within a degree of the variable. The star a is DM. + 19'3439, b is 19°3494, and ʼn is 19°3484. The larger scale chart gives enough of the stars from the 6th to the 12th magnitude within 10' of the variable to identify it in its fainter stages.

COMPARISON STARS FOR ANDERSON'S NEW VARIABLE IN HERCULES.

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The magnitudes of the comparison stars are merely approximate, for the purpose of identification.

The variation of this star has been somewhat rapid, as the following list of observed magnitudes will show,

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