| Semi-axis major | 0·84 | |
| Eccentricity | 0·28 | |
| Perihelion distance | 0·60 | |
| Inclination | 84° | |
| Period | 281 | days. |
| Motion, retrograde. |
The earth moving at the rate of 68,000 miles per hour, is at least five days in passing entirely through the ring. This gives a thickness of more than 8,000,000 miles.
The result of Professor Newton's researches on the orbit of this ring, though undertaken with inadequate data, and hence, in some respects, probably far from correct, is nevertheless highly interesting as being the first attempt to determine the orbit of shooting-stars. More recent investigations have shown a remarkable resemblance between the elements of these meteors and those of the third comet of 1862. The former, by Schiaparelli, and the latter, by Oppolzer, are as follows:
| Meteors of August 10th. | Comet III., 1862. | |
|---|---|---|
| Longitude of perihelion | 343° 38′ | 344° 41′ |
| Ascending node | 138 16 | 137 27 |
| Inclination | 63 3 | 66 25 |
| Perihelion distance | 0·9643 | 0·9626 |
| Period | 105 years(?). | 123 years(?). |
| Motion | Retrograde. | Retrograde. |
This similarity is too great to be accidental. The August meteors and the third comet of 1862 probably belong to the same ring.
III. The Meteors of April 18th–26th.
The following dates of the April meteoric showers are extracted from Quetelet's table previously referred to:
| 1 | A.D. 401, | April | 9th. |
| 2 | 538, | " | 7th. |
| 3 | 839, | " | 17th. |
| 4 | 927, | " | 17th. |
| 5 | 934, | " | 18th. |
| 6 | 1009, | " | 16th. |
| 7 | 1094, | " | 10th. |
| 8 | 1096, | " | 10th. |
| 9 | 1122, | " | 11th. |
| 10 | 1123, | " | 11th. |
| 11 | 1803, | " | 20th. |
| 12 | 1838, | " | 20th. |
| 13 | 1841, | " | 19th. |
| 14 | 1850, | " | 11th–17th. |
The display of 401 was witnessed in China, and is described as "very remarkable." That of 1803 was best observed in Virginia, and was at its maximum between one and three o'clock. The alarm of fire had called many of the inhabitants of Richmond from their houses, so that the phenomenon was generally witnessed. The meteors "seemed to fall from every point in the heavens, in such numbers as to resemble a shower of sky-rockets." Some were of extraordinary magnitude. "One in particular, appeared to fall from the zenith, of the apparent size of a ball 18 inches in diameter, that lighted the whole hemisphere for several seconds."
The probability that the meteoric falls about the 20th of April are derived from a ring which intersects the earth's orbit, was first suggested by Arago, in 1836. The preceding list indicates a forward motion of the node. The radiant, according to Mr. Greg, is about Corona. The number of meteors observed in 1838, 1841, and 1850, was not very extraordinary. Recent observations indicate April 9th–12th as another epoch. The radiant is in Virgo.