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Krüger, of Helsingfors, and laid before the Finnish Society of Sciences. This investigation is of the more importance that doubts had lately been raised whether the effects produced by Jupiter, on the motions of some of the small planets, did not lead to a smaller mass of the disturbing planet than that determined by Airy and Bessel (both of which closely agree together) from the effects produced on the motions of his own satellites. Mr. Lynn entered in detail into the history of the previous determinations, by which it appeared that the mass usually adopted prior to the year 1841 was that deduced by Nicolai from observations of the planet Juno, and which amounted to 1053.924 of that of the Sun; that Mr. Airy, in the Report to the British Association at Oxford in 1832, pointed out the desirability of re-determining it by the elongations of Jupiter's satellites; since the only value then existing found by this, the readiest of all means, was one made by Pound and adopted by Laplace, of which no account remained except the mere statement of numbers in the 'Principia ;' that Mr. Airy afterwards executed this himself, and determined the value 1 which he made known to the Astronomical Society in 1837; and that Bessel in 1841 confirmed this by obtaining the value 1047.87, which was usually adopted afterwards by the German astronomers. It is very satisfactory then to find that Herr Krüger, from his elaborate investigations into the motions of one of the minor planets, Themis, of which Mr. Lynn gave an abstract, was conducted to a value of this element amounting to 104716 almost exactly equal to the mean of the values deduced by Airy and Bessel from the motions of the satellites.

1046.779

Major Tennant observed that his predecessor at Madras, Capt. Jacob, had determined a mass of Jupiter almost identical with that of Mr. Airy, from the satellites.

A Catalogue of Micrometric Measurements of Double Stars: by the Rev. W. R. Dawes.

This included all measures obtained between the close of Mr. Dawes' second series and the present time. The catalogue is preceded by a description of the various micrometers employed. Mr. Hodgson said that a more interesting or valuable series of observations had never been brought before the meeting.

The President coincided in the great value of this series of observations, and said that Mr. Dawes had prepared it at his request, although only just recovered from very serious illness.

Mr. Balfour Stewart, On the Spotted Activity of the Solar Disc. In his work on the solar spots, Mr. Carrington had given a table showing the space occupied by these appearances. This area has lately widened out, to which Mr. Chacornac had also lately called attention. The subject was now about to be investigated more completely with regard to its verification: it had been proved by

observation that when the planet Venus is opposite to the Solar Equator the spotted area is nearest thereto. In answer to some questions of the President, Mr. Stewart stated that it was proposed to investigate the matter more closely, in order to find out the effect of Venus on the solar spots. Attention had not yet been turned to Mercury for the same purpose, but probably would be; in the meantime it was thought, with some show of reason, that a clue to the cause of these outbreaks had been obtained.

A paper On Micrometer Adjustments: by Mr. Simms.

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Mr. Hodgson called attention to the Annals of the Dudley Observatory, containing an oration by the late Mr. Everett, a portion of which he read to the meeting, which then adjourned.

THE NOVEMBER METEORS OF 1866.

As

THE brilliant display of meteors on the night of the 13th-14th of November was seen to great advantage by a large number of observers. From this place, looking south, they shot across the sky incessantly during the time we observed them (from 12 o'clock until half-past 2), their principal direction being from east to west, across and through the constellation of Orion; but numbers were also seen as high as the zenith, and low down in the horizon. the constellation Leo rose, the point from which the meteors commenced their flight became well marked; numbers of them travelling in the opposite direction to those first observed, many descending vertically, but the greater proportion described an arc from east to west. Their general character was that of the usual shooting star, with an exceedingly bright head, leaving a train of white or greenish light to mark the path of the fireball; a marked feature was the persistence of this train for a sensible time after the disappearance of the meteor. One which we noticed about half-past I o'clock, continued visible like a nebula for upwards of a minute, forming the westerly apex of a triangle with Rigel and Aldebaran. This meteor was very large, the head bursting with bright dazzling light and throwing off showers of sparks like a rocket. duration of visibility of the meteors was about three seconds; the smaller and fainter ones travelling faster than those which were more brilliant. At many times several meteors were seen as it were racing across the sky together in parallel lines, and the effect was curious in the extreme as they became visible through the patches of cloud with which the sky was at one time partially covered.

Downs Road, Clapton, 1866, Nov. 20th.

The mean

TO THE EDITOR OF THE ASTRONOMICAL REGISTER. DEAR SIR,-Between midnight on the 13th and 14h. 13m. 10s. (G.M.T.), 2,800 meteors were counted by myself and one assistant in the eastern hemisphere. Another assistant looking out to the west counted nearly 400 in an hour, but became so bewildered by 6 or 7 bursting out almost simultaneously, and this repeatedly, that the attempt to count more was given up. I have no doubt, from what I saw myself in the western hemisphere, there must have been at least 700 visible in the 24 hours. Adding to these 75 which were seen before midnight, and we have upwards of 3,500 in all, up to about a quarter past 2 in the morning.

Some were brighter than Venus ever is; but none were at all comparable to several which appeared in 1832, November 12th, of which, however, I have never met with any good or particular I remain, your obedient servant, W. R. DAWES.

account.

Hopefield Observatory, Haddenham, Bucks:

16th November 1866.

The Meteoric Shower, observed at Teignmouth, South Devon: Lat. 50° 32′ 49"; Long. 13' 58"9 W.-Station-Drawing-room window (circular) facing SE. by S.-Not above one-third, I think, of the heavens came fairly under vision. Soon after 11 P.M. on the 13th my son reported having seen, within a few minutes, fifteen meteors (amongst them a large blue one). They soon multiplied exceedingly. From about 11h. 55m. to 12h. 25m. (half an hour) my son counted 130. This must have been within the mark. From 12h. 25m. to 12h. 45m. (20 minutes) he counted 186. From 1h. 8m. A.M. to 1h. 18m. (10 minutes) he reckoned 210. Probably not a few were omitted, as their great number and the simultaneous appearance of many in different quarters made it difficult to reckon all. From 1h. 20m. to 1h. 25m. A.M. (5 minutes) he counted 189. This was the richest period; meteors were streaming in all parts-two, three, four, and more being often together-many parallel with and near each other, and very brilliant. Their ordinary paths, for some time, with respect to the horizon, were, rising from the east, through the south, and falling in the west. Of the larger, red seemed to me the more frequent colour, but many were blue: their paths mostly straight; the longer sometimes slightly curved, and some of very short tracks a good deal curved at disappearance. I noticed a few with motion direct; but the direction of the great mass was E. to W. at various inclinations; and as Leo came within view it was easy to see that the greater number radiated from that constellation. At intervals the sky was overcast with clouds, and heavy squalls with rain came on. At 1h 8 m. A.M. there was an appearance of sheet lightning in a large cloud; probably the effect of a large meteor behind it. This occurred several times afterwards. From 1h. 57m. to 2h. 2m. A.M. (5 minutes) my son counted 36 meteors. Their frequency was becoming considerably lessened. From 4h. 8m. to 4h. 153m. (7 minutes) I saw only seven. Of the few I noticed moving direct, was a small one in the middle of Orion, about 12 h.; one towards Leo, from below Mars, about 2h. 15m. A.M.; and another towards Leo, from Mars, about 3h. 59m. A.M. Even during the richer period of the

exhibition, there seemed to be lulls or intervals of comparative fewness of meteors, lasting for several minutes. Perhaps the two hours from 12 to 2 A.M. comprised the fulness of the shower.

We did not move from the station we took up to any other, and therefore an immense number on the other side of the house escaped notice; but light overhead often indicated large meteors out of the field of our review. The following table gives the times and places of the disappearance (in general) of a few of the larger meteors. The time is approximate to the tenth of minutes, Greenwich mean time. In some instances the train of light lasted a very short time after the disappearance of the meteor, but generally nothing remained. In some of the very brilliant meteors, sparks seemed to be thrown out at the moment of vanishing :

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A great many fine meteors were seen besides the above; but those were selected to be timed whose path, in the vicinity of some conspicuous star, or towards or from it, might perhaps enable it to be identified by observers elsewhere. After the last of the above registered, I discontinued the lookout. Indeed, I believe the best part of the spectacle had long been over, as above remarked. All the times specified are Greenwich mean time; and the table may, I think, be depended upon as correct within a tenth of minutes, and sometimes nearer.

Many red meteors appeared at very low altitudes over the sea horizon. Some very fine ones streamed downwards from Aldebaran towards the west; and very many passed over Orion. As Leo rose higher in the heavens, the radiating of the meteors generally conformed to it. Several times the converging of meteors in quick succession around this constellation was very striking-they seemed to radiate from it in many directions. The spectacle was a very beautiful one, and must have amply repaid those who, no doubt. in many places were watching for it. GEORGE J. WALKER.

Teignmouth: Nov. 14, 1866.

Sir, I beg to suggest to you the propriety of arranging for the publication of a complete register of observations on the magnificent display of meteors which took place on the evening of the 13th and the morning of the 14th of the present month. The interval of a month would afford an opportunity of receiving reports, not from England only, but from all parts

of the civilised world, and such a register would prove of great value in the elucidation of any theory by which their occurrence is supposed to be accounted for. The record of phenomena witnessed, and inferences drawn, might be preceded by a brief statement of scientific opinion relative to meteors prior to the present visitation. I am, yours respectfully,

Newcastle-on-Tyne: Nov. 15, 1866.

T. P. BARKAS.

We have received in addition a great number of slips from local papers descriptive of the meteor shower, for which we beg to thank our correspondents; our space will allow us to give but short extracts:

Mr. Hind observed vivid lightning during the night, the last time at 3h. 54m. A.M., from below the radiant in Leo. The meteors were not particularly remarkable either as regarded brilliancy or persistence of the trains, few of which remained visible more than three seconds. M. Du Chaillu, assisting Mr. Hind, thought the meteors fell short in these respects of those he had witnessed in Africa at the April period. 1634 meteors were counted between 12 o'clock and seven minutes past 1.

Mr. G. F. Burder, of Clifton, noted the comparative uniformity of size of the meteors, and the absence of any of the largest class. The trains seldom lasted more than two and never more than ten seconds. At one time 80 per minute were counted.

Mr. Harris, of Southernhay, near Exeter, in conjunction with his son, counted 129 between 11 and 12 o'clock, after which they became too numerous to record. At 1h. 15m. a very bright meteor burst, leaving a train which lasted for a quarter of an hour, of which train Mr. Harris made a sketch. This meteor caused a light as bright as daylight for a moment.

Capt. W. Noble, at Maresfield, had prepared a MS. map in order to mark down the paths of the meteors, but found it practically valueless for that purpose, so incessantly did they shoot across the sky. About 13h. 12m. 20s. (but for the fact that the ærolites did not all fall, but radiated from the well-known point in Leo) it might have been “snowing fire." About 13h. 20m. 1os. a splendid one burst to the SW. of the Pleiades, leaving a train which lasted upwards of five minutes by the observatory clock, and which gradually contracted into a fusiform mass, like 31 M. Andromedæ, and then into a more amorphous one, finally disappearing while a cloud went over it.

Mr. Lawton, of Hull, saw the first meteor at 11h. 6m. At 12h. 41m. observed one which appeared visible for several seconds after it exploded. From the combined observations of several persons, looking in different directions, Mr. Lawton makes the number of meteors to have been 144 per minute for 19 minutes, from 12h. 58m. to 1h. 17m.

Mr. F. Bird, of Birmingham, says the meteors were, for the most part, of moderate size, and the explosions unaccompanied with noise, but resulted in the formation of a highly luminous vapour, which remained visible for a few seconds. Some, however, left a more permanent streak, which, being examined with the telescope, was found to be in perfect focus with the stars.

Mr. Thrustans, of Wolverhampton, counted 800 meteors in 30 minutes. At 12h. 40m. observed one near Regulus, nearly as bright as the full moon, which left a faint light in its place for some time.

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