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interest, and which at the present moment occupies the serious attention of the most able astronomers.
“ This return of the comet," says M. Encke, in a memoir recently published, “may enable us also to determine the mass of Mercury, which is at present uncertain, not perhaps immediately, but at some future time, when future re-appearances of it shall enable us to assign with greater accuracy its other elements.”
La Place has regarded this mass, in the sixth book of Le Méca. nique Celeste, as a little less than the two millionth of that of the sun, by extending hypothetically to Mercury the remark which had been made relatively to the Earth, Jupiter, and Saturn, that their densities are almost in an inverse proportion to their mean dis. tances from the sun.
Dr. Olbers has remarked, that of all the celestial bodies which move in circular or elliptical orbits, there is no one which approaches so near to Mercury as this comet, their least distance possible being only the eighteen-thousandth of the mean distance between the earth and sun, or 621,270 leagues.
In previous appearances of this comet there has not been any remarkable approach of these celestial bodies; and in consequence, the value of the mass of Mercury, from the effect of perturbations dependent on the action of that planet, could not then be determined.
But as the two bodies, on Aug. 23, 1835, were only one-twelvehundredth of the mean distance between the earth and sun, or 4,141,800 leagues from each other, variations in the elements of the comet which result from it are sufficiently large for its next passage to its perihelion to occur one-tenth of a day sooner without the action of Mercury. The comet's proximity of the earth will render the effect of these perturbations on the geocentric position of the comet more sensible, and the following variations at the time of its greatest visibility will be the result: Right Ascension.
7 min. 26 sec.
17 min. 12 sec.
16 min. 50 sec.
Decreasing 12. 41 min. 48 sec.
8 min. 16 sec, 23. 24 min. 33 sec.
8 min. 22 sec. Mere comparison, then, of observations with the ephemeris will almost suffice to decide if there do exist any considerable error in the mass which has been assigned to Mercury. Hereafter, when the instant of its passage to the perihelion, as much as it depends on other circumstances, shall be determined to a hundredth, or perhaps to a thousandth, of a day nearly, precise limits for the value of this mass will be obtained.
I have accompanied this map with a table, which gives 76 geocentric positions of the comet in right ascension and declination, answering to mean time at Berlin, or to 28 minutes and 58 seconds after mean time at Geneva. By the side of these, in leagues of 2282 French toises, are the distances of the comet from the earth and sun, deduced from logarithmic values given in Bremiker's ephemeris.
On consulting this table, it will be seen that on the 1st of August, the date of its commencement, the distance of the comet from the sun will exceed 76,500,000 leagues, and its distance from the earth 66,500,000; that, on the 30th of the same month, its distance from the sun will be reduced to 66,000,000 of leagues, and its distance from the earth to 44,000,000 and one third.
It is not till toward the end of August, or the beginning of September, that we can hope to discover the comet. But, as at that time it will rapidly approach the earth and the sun, on the 19th of September, its distance from our globe will be reduced to about 30,000,000 of leagues, and its distance from the sun to 58,000,000; so that from that time, toward the early part of September the comet will be most favorable for observations.
It is on the 7th of November that the comet will arrive at that part of its orbit nearest to the earth: on that day it will be distant from us only 7,565,600 leagues; and on the 19th of December, at the time of its nearest approach to the sun, its distance from that planet will be reduced to 11,480,000 leagues; but then the comet, having attained its maximum velocity of motion, will rapidly leave us and the sun, not to reappear till the spring of 1842. Geneva, July 14, 1838.
L. F. WARTMANN.
CORRESPONDENCE OF THE JOURNAL OF COMMERCE. [By the annexed communication from New-Haven, it will be seen that Encke's comet has been seen there, and that it is visible to the naked eye.]
New Haven, Nov. 19, 1838. Encke's comet has been visible to the naked eye for two weeks past. It was distinctly seen on Saturday evening last, by many persons in New Haven, and resembled a hazy star of the 5th magnitude; its general location was midway between a and B Ilerculis, 3. deg. toward d; or, more exactly, at 6 h. 52 min., mean time, its AR was 16 h. 54 min.; N. dec. 20 deg. 30 min. by estimation, near 287 and 292 of Piazzi's 16th hour, and which pointed nearly toward it. In an ordinary night-glass it presents a fine cometary appearance. It was viewed and located exactly by means of our 14 ft. Herschellian. Should we be fortunate enough to obtain a catalogue of the stars by means of which it was posited, its place might be accurately determined. In the above instrument, which has an aperture of one foot, the comet presented a magnificent spectacle; a nucleus and coma were easily seen, appearing not unlike a sector of 140 deg. The coma was directed toward the sun; its estimated extent was 9 min. The comet is proceeding toward 43 · Herculis, which it will pass, and perhaps occult, on the 21st of this month. Dec. 1st, its AR will be 16 h. 5 min. 53 sec. 4; S. Dec. 4 deg. 50 min. 43 sec. 9, making an isosceles triangle with e and 8 Ophiucii, passing a of the same constellation on the 25th of November. H. L. S.
[P. S. Since the above was in type, we have received the following communication from Professor Smith, of Wesleyan University, Middletown.-Eds. J. C.]
Wesleyan University, Nov. 17, 1838. Messrs. Editors, - Not having an ephemeris of Encke's comet, I have hitherto made no effort to find it. Aided, however, by the article from the pen of Professor Wartmann of Geneva, published in your paper of the 15th, I readily found it this evening near 54 Herculis ; nearly in a straight line joining delta and i of the same constellation, and about three-sevenths of their distance from the former. It has a nebulous appearance, diminishing in brightness from the central portion, and gradually fading away into invisibility. This diminution of light, however, is much more rapid in the direction opposite the sun-giving to it somewhat the appearance of a tail directed toward the sun. Its change of position was very perceptible during the short time it was above the horizon. No stars were seen directly in its path-the extreme parts of the nebulosity, however, swept over two very small ones a little to the south of it. It may not be out of place to call attention again to the fact, that, on the 21st inst., it will pass near and perhaps over i Herculis, and, on the 25th, near Lambda Ophiuchi. Its rapid approach to its perihelion, and the short time it remains above our horizon after sunset, afford little ground to expect to be able to observe any occultations of stars by it later than this present month. Very respectfully yours,
A. W. Smith.
RECENT PUBLICATIONS. The Episcopal Controversy Reviewed. By John EMORY, D.D., late one of the
Bishops of the Methodist Episcopal Church. Edited by his Son, (Robert Emory, Å. M., one of the Professors in Dickinson College.] From an unfinished Manuscript. To which is added " A Defense of our Fathers," by the same Author. Filih Edition. Mason & Lane, New-York, 1838. pp, 183, 154, 8vo.
These two works, now elegantly printed and neatly bound together in one octavo volume, make a very excellent manual on the subject of episcopacy, to which the reader may always refer with high satis. faction. In the “ Episcopal Controversy Reviewed,” the same extent of learning, the same clearness, closeness, conciseness, and cogency of reasoning, and the same felicitous, determinate, and appropriate use of terms are distinguishable, as in all Bishop Emory's productions. Those who knew the bishop, remember well how, in his oral commu. nications, he excelled almost all other men in the clearness of his views, the precision of his language, and the justness of his conclu. sions; and they will be pleased to see with what perfect ease he has disposed of the arguments of Bishop Onderdonk and others in favor of high-toned episcopacy. Price of the work $1.75.
The following note occurs on page 180 of the “ Episcopal Con. troversy Reviewed :"
“ It is related of the late venerable Dr. Pilmoor, of Philadelphia, that, after he had become a minister of the Protestant Episcopal Church, he was in a large mixed company, among whom were some of his old friends of the Methodist Episcopal Church, when he rather
tauntingly indulged himself in self-gratulation on the promise of Christ's presence with his ministers of the regular apostolical succession, of which he had now the happiness to be one. An old friend, who had often heard him preach in the demonstration of the Spirit and of power, when he was a plain Methodist preacher, said to him, • Dr. P., perinit me to ask you one question, as a candid Christian man. When I heard you, as a Methodist preacher, preach to the multitude on the race-ground, the judges' stand being your pulpit, was Christ with you or not? The doctor paused, and then emphatically answered, • Yes, if ever he has been with me, he was with me then.' His old friend was satisfied, and so were the company. It was the candid confession of a plain, honest man- —which plain honest men knew how to appreciate.”
The above works may be had separately, if desired. The first part, containing the likeness, at $1.25.—The “ Defense” at $1.
Christian Biography, Vol. IV. Edited by Thomas Jackson, President of the British Conference-containing the lives of the Rev. Samuel Pearce, of Birmingham; Rev. John Shower, of London ; Mrs. Agnes Beaumont, of Edworth, Eng. ; and a brief memoir of Mr. Samuel Newell, the husband of Mrs. Harriet Newell, so well known in the annals of American female biography. Price 50cts. Mason 4 Lane, New York, 1838. pp. 307, 18mo.
Advice to a Young Convert. In a Series of Letters on Practical Christianity. By the Rev. Leroy M. LEE. Mason & Lane, New-York, 1838. pp. 399, 12mo.
The letters are fourteen in number. Letter 1 contains the Intro. duction ; 2. On Temptation ; 3. Watchfulness ; 4. Prayer ; 5. Private Prayer; 6. Fasting; 7. Self-Examination ; 8. The Life of Faith; 9. Christian Holiness; 10. Church Fellowship; 11. The same Subject continued; 12. The Duties of Church Members ; 13. Brotherly Love; 14. Conclusion.
This work is published on the recommendation of the Virginia Annual Conference. The subjects on which it treats are of the first importance to the young convert, and it is hoped that the work will meet with an extensive circulation.
A concise Dictionary of the Holy Bible. By the Rev. Jas. Covel, Jr., A. M.
Designed for the Use of Sunday School Teachers and Families. With Maps and numerous fine Engravings. Mason & Lane, New-York, 1838. pp. 536, 18mo.
Not long since it was said to us, “ With all your dictionaries pub. lished at the Book Room and elsewhere, we have not one good Bible dictionary that we can refer to.” This objection is now taken away by the work before us. Covel's Bible Dictionary has been prepared with great care, and at much labor and expense. In his preface the author says, “ Geographical articles have received particular atten. tion; no fact is stated but on the latest and best authority. Respect. ing the engravings, the reader may rely on their accuracy also.
No pains or expense has been spared to procure those which are correct; and they are executed by one of the best artists in our country." The engravings are certainly very fine. The work is also neatly printed, and on good paper, and forms a very complete pocket com. panion, which ought to be in the possession of every young preacher, Sabbath school teacher, and Bible class pupil in our connection.
Just Published: A History of the Methodist Episcopal Church: in 2 rols., by NATHAN
BANGS, D. D., vol. 1: from the year 1766 to the year 1792. Mason & Lane, New-York, 1838. pp. 371, 12mo.
RICHARDSON's Dictionary.—The publication of this elaborate work is now completed, in 30 numbers, of about 70 quarto pages each. Consequently the whole number of pages is over 2000. A prominent characteristic of this dictionary is, that the meaning of each word is illustrated by examples from standard authors. The etymology of words is also traced with sufficient minuteness, and in a manner which indicates great research, as well as an extensive acquaintance with the primitive and cognate languages with which the English is connected. It would be invidious to draw comparisons between the merits of this work and others of corresponding claims; but we may say at least, that it imbodies a vast store of philological learning, and “ deserves well of the Republic.” The publishers are Wm. Pickering, of London, and William Jackson, of New York.—Jour. of Com.
Cæsar's Commentaries on the Gallic War; and the first Book of the Greck Paraphrase ; with English Notes, critical and explanatory, Plans of Batlles, Sieges, g-c., and Historical, Geographical, and Archeological Indexes; by CHARLES ANTHON, LL. D. Harper & Brothers, New-York, 1838. pp. 493. 12mo.
A System of Greek Prosody and Metre, with Illustrations of Choral Scanning in
the Dramatic Writers; by CHARLES Anthon, LL. D. Harper & Brothers, 1836. pp. 270. 12mo.
Notes, Critical and Practical, on the Book of Genesis, by GEORGE Bush, Professor
of Hebrew and Oriental Literature, New-York City University: in two rols. Vol. I, pp. 364, 8vo. E. French, No. 146 Nassau street.
NEW PERIODICALS. THE APOLOGIST.-A weekly religious periodical in the German language, published at Cincinnati, O., by J. F. Wright & L. Swormstedt, Book Agents, and edited by Rev. J. Nast. First number on the 1st of Jan. inst.
AFRICA'S LUMINARY - A semi-monthly paper, to be published in Monrovia, Colony of Liberia, Africa, by direction of the Board of the Missionary Society of the Methodist Episcopal Church. Edited by Rev. J. Seys, Superintendent of the Liberia Mission.
Orders for both these publications may be forwarded to the Agents of the Methodist Book Concern, 200 Mulberry street, New York.