January 4, 1900J 



NA TURt 



22 



following morning of November i6th, which, as reported in the 

 Times of November 17th, were both about 2 : l.^ 



One of the forty unconformable or noit-Leonid meteors seen 

 at Littlemore, which appeared at 5h. 40m. a.m. on November 

 15th, was so'extremely bright that it could only be termed con- 

 ventionally an "ordinary" shooting-star, since it was not only 

 brighter than Sirius and than all the other fixed stars, but it 

 left behind it a light streak along its path, the terminal part of 

 which l-emained visible for five minutes. The general hue of the 

 meteor was yellow, inclining to orange, and it described a path of 

 35° from o Ursae Majoris exactly to a (9, or c. Bode) Cainelo- 

 pardi,ox about from 163°, 4-63" to 72°, +66°, in two, or two 

 and a half seconds. A streak remained on all its long path, 

 which thickened greatly in about the last third part, or last 12° 

 of the flight, and remained shining there with surprising per- 

 sistency, while on the earlier part of the track it quickly faded 

 out. The light-wisp shortened gradually from behind, its front 

 end remaining constantly near a (or c) Camelopardi ; and when 

 it had shrunk to about 8° in length, it grew slightly sinuous, as 

 if windwafted, and its last visible light-trace at the end-point 

 of the flight had drifted about half a degree northwards, alto- 

 gether, or sideways from the streak's direction, when it dis- 

 appeared. The first and final appearances which the streak pre- 

 sented near the star a, or Bode's c Camelopardi, are shown as 

 they were represented by a sketch, in the adjoining Figure 



(Fig; I). . 



Like multitudes of streak- leaving meteors which in the morn- 

 ing hours, on all nights of the year, stream from the neighbour- 

 hood of the earth's apex near the east horizon, this bright 





meteor's path diverged from no conspicuously well known 

 ordinary radiant- point of the Leonid epoch, but shot from far 

 east of Leo, and must have passed about over the northern 

 part of Oxfordshire from some radiant-point not far above the 

 E. by S. , or E. S. E. horizon among the stars of Comae Berenices, 

 or near C Virginis and Spica which had then just risen in the 

 E.S.E. Should it have been recorded elsewhere, therefore, 

 descriptions of its apparent path at other places to compare 

 with this one would be of special interest and value, as 

 with only one exception, of a centre of five swift meteors 

 leaving streaks, observed by Mr. Denning on the morn- 



i Until 3h. a.m. on the i6th, the weather in the United States of America 

 had been in general very unfavourable for meteor-watching ; but from about 

 that hour onwards until daybreak, good numbers of meteors, 102, 64, 59 and 

 30, were seen at Philadelphia, Harvard College Observatory, Bayport on 

 Long Island, and Chicago ; and at Denver, as reported in the Times of 

 November i8th, the Leonids, after beginning to appear at ih. a.m., were 

 not very numerous until about 4h. a.m. ; 63 were then counted in a quarter 

 of an hour. The number of meteors seen at Romsey, in Hampshire, was 60 ; 

 and at the Observatories of Madrid and Treptow (Stettin, North Germany), 

 also, good numbers of meteors on the morning of the i6th were recorded. A 

 period of considerable activity of the Leonid meteor-stream seems thus to 

 have very distinctly presented itself on each of the two probably predict-d 

 mornings, for the shower's return, of November 15th and i6th. A lively 

 shower of 80 or 100 Leonids seen on the morning of the 15th by Messrs. 

 Tikhoff and Lespieau in the first of the two balloon ascents made by the 

 astronomers of Meudon and the French Aeronautical Society, on the two 

 foretold shower nights, and a very interesting description by Mr. W. H. 

 Daw, in the English Meehanic of November 24th, of a rapid shower of 40 

 or 50 Leonids seen in exceedingly clear sky on Hampstead Heath, in about 

 40m. between moon-set and daybreak on the earlier one of those two 

 mornings, both perfectly confirm the description given above of a consider- 

 ably bright Leonid display just before daybreak on the morning of 

 November 15th. It must, however, have then very speedily collapsed ; 

 for at Princeton, New'Jersey, U.S., only about 20 Leonids were se>;n, in 

 clear sky, from soon after midnight (about sh.-fih. a m., G.M.T.), until sh. 

 a.m. (loh. a.m., G.M.T.), by Professor C. A. Young, on the morning of 

 November 15th ; (" Popular»AstroBomy," December 1899, vol. vii. p. 543 :— 

 assuming that, in that account of a transitory good view of the Leonids, the 

 date of rain and clouded sky given as the "night of Monday-Tuesd.-iy, 

 November i4th-i5th," may be corrected to November i3th-i4th ; and that 

 by "Tuesday night," when the sky cleared up soon after midnight and 

 about 20 Leonids were seen at Princeton, must no doubt be meant, as the 

 description is regarded here as having been evidently intended to imply, 

 the night of November i4th-i5th). 



NO. 1575, VOL. 61] 



ing of November i6th-i7th, 1885, at 190°, -l-2i°, near (j, or 

 35 Comae, in the southern portion of the constellation ' (pretty- 

 close to which point, through 194°, 4- 23% the present meteor's 

 path-line pas.ses backwards), no radiant point of marked activity 

 near the yearly shower-date of the Leonids, appears, in Mr. 

 Denning's splendidly comprehensive "General Catalogue of 

 Radiant-points," - to have been hitherto recorded in that 

 quarter of the sky.' The altitude of 39° of the latter radiant- 

 point, and its moderate distance, only 45°, from the beginning 

 of the meteor-path, are not entirely inimical to this radiant 

 point's adoption, as although the apparent path was very long 

 for a rather steep-sloped descending real one, it should be 

 noticed that the meteor passed nearly overhead and therefore in 

 such near view at Littlemore that a great apparent length of 

 path may on that ground alone be very readily accounted for, 

 and the thickening and persistence of the streak in only the 

 latter portion of the flight, favours the presumption of a pretty 

 steep descent into the atmosphere, rather than a supposition 

 that the real path was nearly horizontal. The observed speed 

 of flight, 15° or 16° per second, is also too insecure a measure- 

 ment to serve as an exact or very reliable criterion between a 

 higlier and a lower radiant-point position ; but as it was not 

 more than half the apparent speed with which one of the 

 Leonids would seem to dart along, — about 30° per second, — in 

 a similar position relative to its radiant-point and to the horizon, 

 the slower real meteor-speeds of both the a-f Virg-lnids and 

 the q-Comids, — 30-35 miles per second, — owing to their 

 radiant-points' greater elongations from the earth's apex, as 

 compared with that of the Leonids, about 43 miles per second, 

 are evidently represented pretty nearly, although as usual in. 

 estimates of durations of flights and of apparent path-speeds, 

 only with moderate exactness, by the observed, not very rapid 

 angular velocity of the meteor's motion. 



^ The shower is included in Mr. Denning's excellent list of 50 ordinary 

 meteor showers contemporary with the period of the Leonids (wliich wilt 

 soon again be more particularly referred to), as No. 43, at 190°, + 21 . 



2 " Memoirs of the Roy.il Astronomical Society," vol. liii. pp. 203-292. — 

 The 278 shoWfers' numbers in this List, and in its introductory- " Inde.x 

 List " of all the showers' average positions and stellar designations, are 

 quoted in the Tables and general matter of this letter, by the symbol D('99), 

 with the showers' successive numbers. 



3 In a letter from Mr. Denning of November 25th, I am informed that he 

 has been able to compute this meteor's real path from some additional 

 observations sent to him by meteor-recording correspondents from Yeovil in 

 Somersetshire, and from Woburn in Bedfordshire, which accorded very well 

 with the data furnished by the above account at Littlemore. These obser- 

 v.ations he found to be consistent with the supposed direction of flight from 

 the radiant point near q or 35 Comae, and to give a real path which also 

 exactly corresponds with the above conjectured geograf>hical position of the 

 track ; while the vertical height and the length of path agree with the 

 usual results for very bright and slantingly descending meteors. The 

 following are the particulars, in detail, obtained by Mr. Denning, of the 

 meteor's real path. 



The observed duration, of about 2 J seconds, at Littlemore, gives, as here 

 shown, a real speed, 2oi miles per second, so much 'slower than the pre- 

 sumptive one of either 36 or 30 miles per second, which should belong to 

 parabolic-moving meteors proceeding from this radiant-point or from one 

 near Spica, that the measure of duration and of apparent swiftness or 

 slowness of the meteor's flight was really, as surmised above, in this 

 meteor's case as in so many others, not an exact enough datum to be helpful 

 towards a desired, but delicate discrimination of the meteor's radiant-point 

 by astronomical considerations. 



A good view of the meteor obtained by Mr. F. H. Wright, in North- 

 amptonshire, is described in the Enilish Mechanic, vol. Ixx. p. 406, 

 December 15th, 1899 ; Mr. Wright confirms the great visible duration of the 

 meteor's light-streak, by stating that it appeared to change its position 

 slowly from its original line of flight towards N.W., appearing first to be 5° 

 or perhaps more in length, and that after being watched for four minutes, 

 when it was still visible, it appeared to be directed more nearly towards 

 N.E. The point where it " burst, midway between Castor xnA Capella" 

 satisfactorily confirms Mr. Denning's determination of the real height and 

 place of the meteor's end-point ; and as regards the earlier portion of the 

 real track which it pursued, although nothing precise enough to establish 

 the radiant-point exactly, was supplied by the general description that the 

 direction of flight was towards N.W. (more nearly in reality towards due 

 W.), — yet this point's real position near q Comae, had already been certainly 

 determined, and excellently well-defined at that position, by the exact 

 apparent direction of the meteor's course, in Bedfordshire, supplied to Mr. 

 Denning by Mr. W C. Tetley. 



