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Page:Popular Science Monthly Volume 18.djvu/200

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188
THE POPULAR SCIENCE MONTHLY.

in the published catalogues of Heis, Schiaparelli (1872), Weiss, and Konkoly, These include many thousands of paths observed during the period from August 6th to 12th, and such of these as were obviously directed from radiant points situated eastward of Perseus were projected on the star-maps prepared by Professor Herschel for the purposes of the Luminous Meteor Committee of the British Association. In all 762 meteors were thus utilized, and they gave distinct evidence of the positions of a number of active streams in Auriga and Camelopardus, some of which were previously observed by Heis, and many of them have been confirmed by the writer during the last five years. The following list embraces the chief radiants thus deduced:

Meteor-Showers east of Perseus, August 6th-l2th.

No. Radiant.
α δ
No. of
Meteors.
No. Radiant.
α δ
No. of
Meteors.
1 .... 70° + 64° .... 74 10 .... 134° + 77° .... 30
2 .... 61 + 39 .... 59 11 .... 74 + 33 .... 28
3 .... 96 + 71 .... 87 12 .... 104 + 34 .... 13
4 .... 61 + 48 .... 59 13 .... 99 + 46 .... 17
5 .... 51 + 74 .... 62 14 .... 45 + 33 .... 18
6 .... 78 + 56 .... 59 15 .... 76 + 74 .... 20
7 .... 76 + 45 .... 43 16 .... 52 + 20 .... 14
8 .... 50 + 47 .... 42 17 .... 87 + 34 .... 14
9 .... 92 + 57 .... 42 18 .... 87 + 15 .... 8

The relative positions of these showers are depicted in the diagram (Fig. 3), where the more prominent displays of the group are represented by deeper circles than the minor. Some of the latter can not yet be regarded as certainly established, inasmuch as they rest on slender materials.

Heis devoted much attention to the meteors of the August period during more than forty years (1833-'75), and in his extensive "results," published in 1877, gives the following as the chief radiant points for August 9th-llth:

Symbol. Radiant.
α δ
No. of
Meteors.
Symbol. Radiant.
α δ
No. of
Meteors.
A11 .... 45° + 52° .... 233 Cr11 .... 273° + 56° .... 93
B4 .... 330 + 55 .... 164 St12 .... 40 + 45 .... 118
B5 .... 292 + 70 .... 135 St16 .... 56 + 70 .... 105
Cr5 .... 12 + 32 .... 93 St17 .... 27 + 21 .... 70
Cr6 .... 355 + 81 .... 103 St18 .... 25 + 58 .... 282
Cr8 .... 11 + 60 .... 192 St19 .... 295 + 44 .... 110
Cr9 .... 73 + 63 .... 125 St20 .... 51 + 75 .... 133

But, in addition to these, there are a large number of radiants scattered over the sky, especially in the eastern quadrant. One of the most notable of these proceeds from the eastern extremity of Aries (44° + 25°), and supplies some bright meteors in the morning hours; but the most conspicuous shower discovered east of Perseus at this epoch lies in Camelopardus, and in the diagram (Fig. 4) a number of its meteors, falling among the stars of Ursa Major, are reproduced