8
ON THE ORBIT AND PHENOMENA
first seen was about 9 o’clock P.M., and the duration of its visibility about 45
seconds.” 1
DansviUe , New York, Nos. 8, 9, 59, and 178. Nos. 8, 9, and 59 were communi
cated by Prof. J. J. Brown, who says that he asked a number of persons who saw
the meteor, to point out its apparent path, by means of a board, which he had attached
by a pivot to a post, and that they invariably swept the heavens “ through the
zeniththat in size it was spoken of vaguely as “ about the size of the moonthat
one observer said he saw it “run right over that big star” (a Lyrae). In a letter
received some weeks later, he says: “ I have just finished mounting an equatorial
telescope, and the first purpose to which I have applied it is to determine the
altitude and direction of the meteor, in regard to which you wrote me. The mean
altitude of six observers, who were requested to point the telescope to the spot
where the meteor appeared when S. 76° 30' E., is 77° 2'.” No. 178 was taken from
an article in the Rochester Democrat, and communicated by Prof. Chester Dewey.
Danville , Pennsylvania, Lat. 40° 58', Lon. 76° 39'. The following article
appeared in the Pottsville Mining Journal: “Danville, July 21.—A very brilliant
meteor passed over this place last evening at ten o’clock, giving as much light as a
full moon. It came in view at the horizon, west of northwest, and passed due east,
being about six seconds in passing. It went out of sight below the horizon, east
of northeast. When directly northeast, it broke, forming two, one following the
other. Some minutes” (another account says four) “after it disappeared, a sound
resembling thunder was distinctly heard. No clouds were in sight.” 1 2
Davidsonville, Maryland, No. 186. Observed by Henry U. Thorpe, who says
the altitude of the meteor was about 20° when a little west of north; that it
seemed to divide when “a little east of the meridian.” 3
Deep Creek , Virginia, No. 131. Observed by James Smith, eleven miles nearly
due south from Norfolk. He says that the meteor appeared about due north at an
altitude of about 10°, and that it travelled about 30° in about one minute. 4
Delanco , New Jersey, Lat. 40° 4', Lon. 75° 5'. Time, near 10 o’clock. 5
Detroit , Michigan, Nos. 10, 74 and 159. One account says of the meteor, “ It
appeared at 9h. 15m. P.M., 40° above the horizon, 30° west of north, taking an
easterly direction. It moved slowly to the east till it was lost sight of behind a
1 Communicated by Capt. George G. Meade and Lieut. Orlando M. Poe, of the U. S. Lake Sur
vey. According to the calculated path, the altitude of the meteor increased about 1^° during the
first half of its visible track, and then decreased 9^° during the last half. Time of first appearance,
9h. 16m. B sec., and visible 17 seconds.
2 According to calculation, the meteor was 23 seconds in passing from a northwest to a northeast
azimuth ; the time when it passed the meridian was 9h. 37m. 2 sec.; the azimuth at the first explo
sion almost due north, and at the second about N. 79° E. ; and the sound, if it was caused by the
first explosion, should have been heard about 8 minutes after the meteor disappeared.
3 According to the calculated path, the division took place about one-eighth of a second before the
meteor crossed the meridian; but it is allowable to suppose that the separation was not noticed till a
second or so afterward.
4 According to the calculated path, the meteor was 21 seconds in passing from “ due north” to
N. 30° E.
* According to calculation, the meteor crossed the meridian at 9h. 43m. 28 sec.