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New Variable In Dorado.—M. Moe'sta says that he thinks there are grounds for regarding the star p. Doradua as one whose light is variable, liy Lacaille it was set down as a 5th mag.; Brisbane called it a 6th mag.; and in January of the present year it was observed by Moesta as of the 8\ or 9th mag.
Ephemeris Of The Variable S Cancri. — M. Schbnfeld, of Mannheim, has issued the following ephemeris for epochs of minimum light during the next three months:—
1865. October 8 5-1
„ 17 167
» 27 4-3
Crimson Star In Aquila.— Mr. Webb communicates to a contemporary some remarks on the star in—
E. A. Decl.
h. m. s. ° „
18 57 11 5 53
which we here transcribe—"Its aspect is singular and striking, especially as contrasted with its whiter neighbours. The disc is of a rather feeble red, the intensity of light serving perhaps to make its peculiar hue less evident—an effect which I have noticed in other deeply-coloured stars; but the surrounding rays are of a decided crimson cast." The magnitude is about 7J.
The Vacant Canonry At Durham.—This valuable preferment (1,000?. a year), rendered vacant by the death of the Archdeacon of Lindisfarne, has been conferred by the Lord Bishop of the diocese on the Rev. Temple Chevallier, Professor of Astronomy in the University of Durham. Our readers need scarcely be reminded that Mr. Chevallier is a man of large and varied experience in practical astronomy.
Brilliant Meteor.—The following are Mr. A. S. Herschel's notes of a meteor well observed at Collingwood, Hawkhurst, on the 24th September:—"Sept. 24, 1865, 7h. 50m. P.m. Meteor =* Sirius, white or bluish, lasted 4-5 seconds; commenced at Beta Piscium, disappeared at a point midway between Alpha and Eta Aquilee. The meteor sparkled, and was followed by a train of red sparks three or four degrees long, which disappeared with the meteor, and by a slight phosphorescent train which lasted half a second. Length of path 40° —' Radiant Pisces.'" The same meteor was observed by the editor of the Astronomical Register, at Ramsgate, at 7h. 48m., in the SSE., travelling from below Pegasus, across the Milky Way, and below
Aquila, and disappearing just above Jupiter, with which it was equal in size, but paler, and of a bluish tint. Estimated time seconds. It was followed by a train of light about 50 in length. In his note to the editor, Mr. Herschel says that "from a combination of the two observations, the approximate height of this body can be ascertained."
ON AN INSTRUMENT FOR COMPARING COLOURS, PROPOSED TO BE DESIGNATED A HOMOCHROMASCOPE.
By W. R. Bibt, Esq.*
(From the Monthly Notices of the Royal Astronomical Society,
In the course of my observations on the physical characteristics of the moon's surface, I found it necessary to devise some means for comparing with known standards of colour the tints of various portions, especially the dark-floored craters, the extensive grey plains, and the more luminous districts in immediate proximity with the rayed craters. After various trials I found the instrument—of which a somewhat rough model is now exhibited f—the best adapted for the purpose. It is mtended to consist of a moveable cradle, possessing a rack-work motion, receiving one of a series of glass plates; on each plate a certain number of discs are painted with transparent colours, each colour being experimentally determined by means of an instrument similar in its construction and action to the colour top. The numerical value of every tint can thus be precisely ascertained. The cradle with its plate of glass is moved within a box having a circular aperture, top and bottom, exactly equal to the coloured disc; so that, while the strong light of a lamp enclosed in a lantern is thrown on a highly reflective surface attached to the box, the disc is viewed by the light thus reflected and transmitted through it. In this way, while the eye carefully contemplates the tints of the lunar disc, it is also able to compare them with the tints on the glass plates, which being properly arranged and numbered, the tints observed can be easily registered. The instrument, mounted on a tripod, may be conveniently placed near the telescope for observation.
It is highly important that, in all observations with an instrument of this kind, the flame of the lamp should always be of the same intensity. This may be secured by a simple arrangement in the construction of the lamp and the burner; the construction of the instrument ensures permanency of tint in every other respect.
* We insert this paper in reference to a suggestion of M. Chevreul, which will be found in the Astronomical Register for April 1865, p. 114. f The model was exhibited at the meeting.—Ed.
TO THE EDITOR OF THE ASTRONOMICAL REGISTER.
Sir,—It will not have escaped your notice, that a letter lately appeared in the Times from Mr. Lowe, describing the appearance of some celestial object which he conjectured to be Biela's Comet. Upon referring to your Register for July, I there find an ephemeris givmg the position of that body for the whole of that month, and the last position given, oh. 21m. 8s., would lead an observer to look for it soon after sunset, due east, about 100 alt., consequently, very far from the vicinity of the sun. Now Mr. Lowe discovers his visitor near the sun at 8 P.m., Aug. 28, and, one would infer, not far from its perihelion. But Dr. Michez, your correspondent, does not expect the perihelion to be reached before 1866. Some one must be in error m these wide data.
Possibly your number for September, which I have not yet seen, may explain these discrepancies. .
I remain, Sir, vours, Reading: Sept. 5. 'H. H. C.
COMET OF 1865.
Mr. J. Tebbutt, of Windsor, N.S.W., makes some remarks on this comet, which, our readers will remember, was not visible in this hemisphere. He observed it through a considerable period, and has deduced the following elements:—
Perihelion passage, 1865, Jan. 14. 34G.M.T.
O / //
Longitude of perihelion = 141 15 37
Longitude of ascending node =253 3 15
Perihelion distance = 0-026014
Heliocentric motion, Retrograde.
"The elements of Comet V. of 1862 resemble these, with the exception of the place of the perihelion, which differs nearly 1800. A comet appeared about B.C. 371, and the limiting values of its elements have been assigned by Pingre- from an account of it given by Aristotle. They bear some resemblance to those of the present comet; but observations made more than 2,000 years ago are too rough for the settlement of this question. Pour comparisons of the comet were obtained on the evening of March 23 with a star of mag. 7 which is not to be found in the catalogues. The comet was last seen here on the 28th, being then barely distinguishable, although the sky was very clear and the night dark."
The following ephemeris of this body is by M. Moller, of Lund.
Its re-discovery was effected by M. thiele, at Co;
For Berlin Mean Noon.
The comet is in the constellation Aquarius throughout the month. DArrest says that Moller's ephemeris is very correct. The comet resembled, when found, a nebula of the 3rd class: it was nearly round, about 2 5" in diameter, somewhat lighter in the middle, and had a small vet decided nucleus.
The followmg ephemeris of this body is by M. Michez, of Padua:—
For Greenwich Mean Noon.
The comet is in Pegasus throughout the month. On the 29th, it is close to a Pegasi (Markab).
COMET II. OF 1864.
M. Kowalczyk, of Warsaw, has just completed an elaborate investigation of the elements of this comet,-which he finds to be as follows:—
Perihelion passage, 1864, Aug. 15.592, B.M.T.
_ o / //
Longitude of ascending node = 95 12 13
Longitude of perihelion = 246 11 15
Inclination of orbit = 178 7 49
Log. perihelion distance = 9-9586818
Astronomical Occurrences.—Notice.—The first part of the table of occurrences for October, the positions of the planets, and particulars of two eclipses, were given m the September number of the Register.