OBSERVATIONS UPON THE METEORS OF AUGUST. 269 



origin was such as to leave no doubt about their connexion with the shower, 

 and I induced two fellow passengers to aid me in observation. We stood on 

 deck, and divided the heavens by three vertical planes, from the zenith to the 

 horizon, and commenced observation. In the space of forty minutes we reported 

 respectively nine, eleven, eight meteors, 7 or 8 of which did not observe the com- 

 mon radiant. The remainder were, in all important respects, like those described 

 last night. On the presumption that we saw half the visible meteors, the 

 number per hour would be about seventy-three to seventy-five, or one for every 

 five that were visible 23 hours previously. 



The convergency of their lines traced back was manifestly the same as last 

 night, but confirmed the impression I have entertained from the first, that theij 

 do not meet in a common point, but in a radiant region, or circle, which has the 

 sword cluster for its centre, with a radius of 2° of a great circle. 



"I should not omit to mention the notice of two or three meteors from the com- 

 mon radiant, whose light, both of body and train, was of a fiery colour, (differing 

 very much from the remainder in this respect;) and these seemed to falter in 

 their course, and to be retarded till they expired. Are not these evidences of 

 the correctness of my suggestion last year, that these meteors penetrate the 

 atmosphere of the earth? And may not their light and velocity have been 

 modified by atmospheric resistance ? 



They were still visible at a late hour. Weather clear, day hot, evening 

 pleasant, and perfectly calm. 



" August 12th. ■ 



Watched the heavens during the evening, and saw several, but fewer than 

 last night. Nearly all originated as before. Perhaps the centre of the neigh- 

 bourhood of radiation was a little more eastwardly. Several were very splendid, 

 but nothing I saw seemed to require me to observe longer than to satisfy myself 

 that the display presented no new phases. 



« August 13th. 



* * At night took an altitude of Polaris, for the latitude of Peoria, 

 Illinois; and while observing, I saw two meteors with trains, having the usual 

 radiant. I continued watching sufficiently long to be satisfied that the display 

 still continued, but was very much diminished in intensity. One observer could 

 see about six conformable meteors per hour." 



August 9th, 1840. 



On the afternoon of this date I arrived in Philadelphia; and, after some dif- 

 ficulty in search for observers, found Mr. S. C. Walker and others at the obser- 

 VII. — 3 s 



