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Professor Challis: Mr. Glaisher confirms the Cambridge observations. We there often saw the August meteors, but not the November ones.

Mr. Adams saw 120 from 12 to I. Professor Challis had never seen so many in the time, therefore this must have been quite an exceptional case-a complete shower. Mr. Adams made the average height 83 miles; Professor Challis, in August, 1862, made it 82 from 10 coincidences, and the similarity of result was remarkable.

Mr. C. G. Prideaux mentioned that on Primrose Hill he, with two companions, saw 72 in 40 minutes, and 120 when out for one hour and a half.

The President called on Professor Grant, who was present, to give an account of his operations for distributing time in Glasgow, where perhaps a dozen public clocks were controlled from the Observatory; whereas in London we had only one or two.

Professor Grant said that Jones's method of controlling clocks was used, and was most successful. Ordinary clocks were kept correct by an electrical current affecting the pendulum in a way which he described by aid of a diagram.* The battery power was small. At present he had 11 clocks regulated, and should soon have 16 or 17. It had been usual to remove the two seconds pendulums of turret clocks, and put up seconds pendulums, but he found the long ones as easily regulated as the shorter, and of course they were very preferable in other respects.

Mr. Pritchard said that at Glasgow and Edinburgh these accurate clocks had put the watchmakers on the qui vive, and they now made much better timekeepers than they used to do, and he wished the system could be extended to London. The meeting was then adjourned till January.

CORRESPONDENCE.

N.B. We do not hold ourselves answerable for any opinions expressed by our correspondents.

BRIGHT SPOT ON THE MOON.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-On the 24th ult., I was observing the moon, about half-past 6 P.M., when I noticed that the dark side thereof was more than usually clear and

Our readers interested in the distribution of time signals, should refer to a most able lecture on that subject delivered by Mr. Ellis, of the Royal Observatory, before the Horological Institute, and reported at length, with the necessary diagrams, in the Journal of that Society.

distinct making a sweeping survey over that part, my eye almost immediately caught a very pretty speck of light near the lower limb, towards N.E., very much like a star of the 8th mag., but quite distinct and clear.

I observed it for about an hour and a half, until the moon was out of my reach. I tried different eye pieces, &c., and found it better with 60 and 80 than anything higher, although it was well seen with even 200.

I took as much care as I could-in the absence of proper apparatus-to ascertain its exact position, and believe it must be No. 128 in Webb's Map of the Moon, or very near to it. The terminator ran across the Apennines, about No. 86 of the said map; the moon's age at the time being 6 days and about 6 hours, and about 6 or 7 hours past her greatest libration NE.

My O.G. being 4-aperture, from Solomons'.

I may also mention that I showed the speck in question to a friend that happened to be present; and one of my daughters, whose eye has had some practice with the telescope, found it quite independent of my directions. If you think the above of any interest, you can make what use thereof you may think proper.

Pwleheli:

I am, Sir, truly yours,

W. O. WILLIAMS.

Dec. 12, 1865.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL

SOCIETY.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-At the last meeting of the Royal Astronomical Society the "Monthly Notices" for the previous meeting were not in the hands of the Fellows. The President, indeed, had a copy, which he stated to contain errors in the report of his remarks.

May I ask the officers of the Society, through the medium of your pages, why the Monthly Notices cannot be prepared earlier? This is not the first time that such a delay has arisen, and some reason should be given; for it is impossible for the Fellows who have been unable to attend the previous meeting to comprehend properly what is taking place, unless they are acquainted with the papers read the month before. I am, Sir, truly yours,

F.R.A.S.

Dec. 16, 1865.

BINOCULAR EYE-PIECES.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-In the early part of this year I saw in Silliman's American Journal of Science a notice of a binocular eye-piece which could be applied to any microscope, and rendered the addition of a side tube unnecessary.

In the usual binocular microscope, a prism placed immediately above the objective reflects the rays proceeding from the object in two directions, requiring another "body" to be added.

But, in the new eye-piece, the rays of light being divided at the base of the cone instead of the apex, the prism is placed at a distance from the objective, the eye-piece itself containing the two bodies, the prism occupying the place of a field lens common to both, causing the rays to pass through the tubes to both eyes.

This may be used with any microscope, by withdrawing the uniocular eye-piece and simply inserting the binocular in its place.

It has struck me that an eye-piece of this kind might be used with the telescope, and would be the cause of great comfort to those who are engaged in observations which are continued for a long time. The being able to use both eyes is a very great desideratum; for the use of one eye only for a long time is not only painful but injurious. A little light might be lost, but that, when compared with the gain of ease and comfort, would be of little importance.

When in London last week, I called on several of the well-known opticians, but they told me that they knew nothing of the eye-piece I have mentioned.

I have, therefore, ventured to trouble you with this letter, hoping to be able to gain some information on the subject from some of your correspondents or readers, who I am sure will agree with me that a good binocular telescopic eye-piece would be a great boon to observers. I am, Sir, yours faithfully,

C. S. HARRIS.

Dec. 9, 1865.

EPSILON LYRE.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-I beg to enclose a diagram of e Lyræ and its companions, as seen by me last month. I regret I have mislaid the date. The night was dark, and the atmosphere was remarkably clear. I cannot always see all the stars here marked, but I have occasionally, and on that night I could fancy I detected 2 or 3 other minute points of light, not inserted here. The diagram is only a rough approximation, as I have no means of measuring. The telescope is a 7-inch achromatic, by Troughton and Simms, 9ft. 6in. greatest length. The power used 146.

I am, Sir, yours truly,

St. Bartholomew's Parsonage, Southsea :

Dec. 12, 1865.

N. S. GODFREY.

[Mr. Godfrey's diagram shows four small stars in addition to those seen by Mr. Dawes. See Reg. vol. 2, p. 302, fig. 2.—ED.]

DETERMINATION OF THE LONGITUDE,

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir, D. T. K. enquires, in your last number, what is the best method of determining the longitude with the telescope (equatorial) without trigonometrical calculations. Lest any one of more experience should not answer the question, may I be permitted to inform him that the best method-and a very simple one-of so determining the longitude is by means of Moon Culminations, as described in the Nautical Almanack (p. 528 of this year), in Loomis's Practical Astronomy, 5th edit. p. 312, and in Chauvenet's S. & P. Astronomy, vol. i. p. 350. I am, Sir, your obedient servant,

Mentone, Alpes Maritimes:
Dec. 13, 1865.

D. A. FREEMAN.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,—D. T. K., in your last No., enquires what is the best method of determining the longitude with a telescope equatorially mounted, without trigonometrical calculations. I don't know how far a well-constructed equatorial might be capable of being used for taking the meridian passage of the moon and moon-culminating stars. Perhaps with care and precaution a tolerable approach to accuracy might be thus obtained.

The eclipses of Jupiter's satellites, especially of the first, often give excellent results; but here, of course, a knowledge of the true time is necessary, and a little trigonometry is requisite in every method of determining that, excepting the observation of equal altitudes of a star, or of the sun when its movement in declination is very small.

Yours, &c.

G. J. W.

URANUS.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-Many of your readers have been looking out since March last for some notice in your periodical of the planet Uranus, which has this year1865-completed one entire circuit of the heavens since its discovery. Some of your friends who have given attention to that planet's movements, and have access to the results of others' labours, would gratify us all by a review of its course, from its discovery in 1781 to its reaching the same R.A. this year. We should like to know when it was first accelerated in longitude by its outside neighbour, Neptune, and when first retarded, &c. We should also wish to know some minor particulars, such as in what years it entered the several constellations, &c. If the review should be accompanied by a diagram, giving two concentric circles, on which would be marked the places of both the above planets at important or interesting periods of the course of Uranus, we would prize it highly. I trust you will allow this suggestion to appear in the Register. It suits it well, as it is found to be a medium through which the skilled astronomer instructs the lovers of astronomy, though only learners, like

Your much obliged correspondent,

THE NOVEMBER METEORS.

SENEX.

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. Sir,-A remarkably abundant shower of meteors took place on the 13th of November last, from midnight on Sunday until sunrise on Monday morning. The meteoric shower, of which this was an annual return, now commonly known as the "November Meteoric Shower," took place in England 33 years ago, on the same date, and at the same hour as this shower of last November. It may interest some of your readers, who were prevented by the lateness of the hour at which the shower was expected to take place from being made spectators of the phenomenon, to be informed that at the Royal Observatory, Greenwich, the shower was well observed during the whole time of its duration. The next occasion when the November meteoric shower is expected to be visible will be the morning of the 13th of November, 1866, and its next return will be, if possible, even more striking than its predecessor in November last. The moon at that time will be below the horizon, and the meteoric shower itself will be at a maximum of intensity of which there will be no repetition after that time for at least 33 years to come.

The meteors began to shoot across the sky towards midnight of November 12th, and continually increased in numbers until towards sunrise on the morning of the 13th. More than 250 meteors (279) were recorded at Greenwich in this time. More than a half of the meteors (142) were equal to or brighter than 1st-magnitude stars, and nearly two-thirds (172) left behind them, on their whole apparent courses, luminous streaks of phosphorescent light, which remained visible two or three seconds after the disappearance of the meteors, fading gradually from the ends towards the

centre.

The colour of the meteors and of their streaks was nearly white from their brightness, but the prevailing hue was blue, and even a greenish cast of colour was observed.

About the hour of 5 o'clock A.M., 25 meteors were counted in 12 minutes in the west and south-west portions of the sky alone, from which their frequency may be estimated at 250 per hour in all the sky. The radiant point of this stream of bright meteors (from which they spread across the heavens in all directions) was a well defined point, very clearly shown in right ascension about 165°, and polar distance about 60°. At the same hour, and with an equally pure sky, the display on the following night was less intense. The display on the morning of the 13th is the finest ever noticed at the Royal Observatory, Greenwich; and it would seem from this circumstance, that this epoch is determined with a good deal of precision.

On the morning of the 13th, during the greatest brightness of the shower, seven meteors were simultaneously observed at the Observatory, Cambridge, and at Hawkhurst, in Kent: the distance between these two places, in a direct line, being somewhat more than 83 miles. The heights of these seven meteors above the earth, at their place of origin or first appearance, obtained by a rapid method of graphical estimation, appear to have been respectively

79, 71, 92, 65, 74, 87, and 114 British statute miles. The average of these quantities (83 miles) differs little from the average height at first appearance (82 miles) of 20 meteors, simultaneously observed on the nights of the 9th and 10th of August 1863. The radiant point of 68 meteors observed at Hawkhurst, from midnight until 3 o'clock A.M. on the morning of the 13th of November, 1865, occupied a position in apparent right ascension 150°, N. declination 20°, not quite 3° from the star Gamma Leonis, from which point as a centre, towards the latter part of the time, the meteors shot with considerable regularity, and with very little deviation.

Collingwood, Hawkhurst:
Dec. 9, 1865.

I am, Sir, your obedient servant,
ALEXANDER S. HERSCHEL.

REVIEW.

ASTRONOMY WITHOUT MATHEMATICS. By EDMUND BECKETT DENISON, LL.D., Q.C. London: Society for Promoting Christian Knowledge. Fcp. 8vo. pp. 193. Two Shillings.

The publication of books like the present is a healthy sign: that is to say, we presume they are issued because they are likely to sell, and that such is the case is a healthy sign. It is a too common notion that a study of astronomy, however cursorily conducted, necessarily involves a considerable familiarity with mathematics, but this is a great mistake: our pages testify to this as well as do those of Mr. Denison. The tyro can become

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