OBSERVATIONS OF LUMINOUS METEORS. 



" Meteors seen August 1871, at Yorlc. 



89 



<' Generally two watching, sometimes three, and once or twice hut one. 

 For the 10th I had a list of twenty-six others handed me, observed by a 

 friend close at hand, of which nineteen were from Perseus. 



"J. Edmitnd Clark." 

 "20 Bootbam, York, August 14." 



At Birmingham the position of the radiant-point appeared to Mr. Wood to 

 have undergone no change from its apparent place as described in former years. 



At Manchester on the 10th, and at Bolton on the 11th and 12th, Mr. Greg 

 noted especially the short meteors near the radiant-point in order to deter- 

 mine, if possible, its real place. On the night of the 10th it appeared to be 

 situated about halfway between r; and x Persei, on the 11th exactly at »j, 

 and on the 1 2th about halfway between jj and y Persei. In relation to these 

 results Mr. Greg observes : — " There can, I think, be little doubt, judging from 

 my own observations, that this year the radiant-point was lengthened out on 

 a line between ^ and y Persei, with the centre precisely at ij (or Ic), that 

 there was a tendency to move with the time from x towards y, and that on 

 the night of the 11th the tendency to accurate radiation was unusually pre- 

 cise. Probably accuracy of radiation is a symptom of a particular shower 

 being at its maximum intensity, with the individual meteors less scattered 

 than at periods of its minimum display. I saw so very few meteors move 

 near the radiant, either up or down, that I cannot so precisely state the 

 position of tlie radiant-point in right ascension as in declination." 



Among the list of meteors received by the Committee from the observers 

 of the August shower in 1871, the paths of 316 meteors noted on the nights 

 of the 9th, 10th, and 11th of August were sufficiently well indicated to be 

 correctly delineated on suitable star-maps. Of the whole number nine were 

 directed from a radiant-point near the north pole of the heavens, at about 

 R. A. 10°, N. Decl. 82°; fourteen proceeded from a radiant-point in Cygnus, 

 apparently close to I Cygni, at about R. A. 293°, N. Decl. 42° ; and thirty-three 

 meteors diverged from radiant-points in or near the constellations Pegasus 

 and Aquarius. Of the remaining number a few meteors appeared to be very 

 erratic or sporadic, and about 250 were distinctly members of the shower 

 diverging from the radiant-point in Perseus. The long duration of the 

 shower appearing to offer a favourable opportunity for ascertaining if the 

 position of the radiant-point underwent a sensible change during the time of 

 its continuance, the recorded apparent patlis of all the Perseids noted during 

 successive intervals of ten minutes on each of the nights of observation were 



1872. H 



