OBSERVATIONS OF LUMINOUS METEORS. 169 



succour and incentive than that of his own unfailing ardour in these investiga- 

 tions) succeeded in surpassing, during the past year, in his own catalogue 

 of meteor-showers the number which any single observer has before been able 

 to chronicle in a protracted time of many successive years of observation. 

 (Sufficient illustrations to describe in full the particulars of the meteor-showers 

 which he observed, and the characters of their appearance, in which he was con- 

 firmed by Mr. Corder's simultaneous observations, and by tho reductions 

 which he contemporaneously made of foreign observers' catalogues, cannot 

 without the aid of tables be presented for discussion in the concise form which 

 the limits of space assigned to this Report require. Comparative Tables of the 

 new meteor-showers and radiant-points, showing the values attached to the 

 observations and the extent to which they agree among themselves and 

 extend or assimilate with earlier determinations, have been arranged and 

 compiled by Mr. Greg, and will be found at the end of this appendix. 



Speaking of his observations in October last, when the 1300 meteor-tracks 

 from which his last published list of 52 radiant-points was constructed were 

 all recorded, Mr. Denning wrote, " I found meteors rather frequent between 

 the 13th and 29th of October. Altogether I watched 23 hours (chiefly before 

 midnight) and saw 155 meteors, of which I recorded 122. Subtracting 2 

 hours of moonlight (when only 4 meteors were mapped), and deducting one 

 sixth from tho time of the watch, during which my attention was engaged in 

 mapping, temporary absence, &c, we get an average horary number of 8-6 

 meteors for October 13th to 29th (p.m.), 1876 ; but I hardly think meteors 

 during this period were more frequent than during the latter half of July, 

 when Cassiopeiads, Draconids, &c. were very active. 



" Confirming a remark which was made some time ago, that the luminous 

 streak of a meteor will occasionally brighten visibly after the actual extinc- 

 tion of the nucleus, I noticed an instance of the kind quite recently. I was 

 looking towards Orion, and had just glimpsed a very faint meteor, almost 

 doubting whether or no it was one at all. While hesitating about it, I kept 

 my eye directed to the same spot, and there, two or three seconds later on, 

 a small train came out very plainly, and enabled me to mark the path of this 

 well-nigh unseen shooting-star most accurately." At 10 h 52 m p.m. on the 

 12th of August, during the Persei'd shower in 1876, Mr. Clark also noticed a 

 nearly stationary Persei'd, as bright as a star of the second magnitude, at 

 32 3 -5, + 58°-7, with a course scarcely longer than |°, which was visible for | 

 of a second, and its streak for two and a half seconds afterwards, very brightly. 

 This shooting-star, Mr. Clark wrote, " looked almost like a double meteor, its 

 streak flared up so brightly." The Orionids (of which the meteor seen by 

 Mr. Denning was probably one) are even more remarkable than the Persei'ds 

 or the Leonids for the breadth or volume and for the brightness of the per- 

 sistent light-streaks which mark their tracks, and the long-enduring or even 

 rekindling lines of light that remain on the tracks of the meteors of these 

 showers indicate their extreme velocity, due to the close proximity of their 

 radiant-points to tho apex of the earth's way. A sign so certain of this pecu- 

 liar situation or proximity to a well-known point in the sky of a meteor's 

 radiant-point is of such essential value in assigning to individual shooting- 

 stars the probable shower-centres from which they emanate, that no ambiguous 

 words should be used, if possible, to describe it ; and in recording any luminous 

 appearance, continuous or interrupted, visible in a meteor's wake, observers 

 would do well to reflect and to state in as unambiguous terms as possible if it 

 presented that appearance of rightly-named " phosphorescence" which is so 

 easily recognized and distinguished by the peculiar property of rekindling 



