THE AUGUST METEORS. 
325 
only meet with, a few meteors in its rapid flight through a zone 
exceeding 10,000,000 miles in width. 
The period of the August meteors is uncertain. Their dis- 
tribution appears to have been so effectual that the element can- 
not be determined. Some years give plentiful showers, but 
there have been no decided traces of regularly recurring maxima, 
as in the case of the Leonids. This may possibly he explained 
by the fact that the period is a long one, and would not become 
defined until after centuries of research. Comet III. 1862, which 
shows an exact resemblance of orbit to this system, was com- 
puted by Oppolzer to have a period of 121*5 years ; and as 
there occurred a fine display of the August meteors in 1863, we 
cannot anticipate its periodical return until about 1964, if the 
calculations are reliable. 
The August Perseids have been more frequently observed 
than any other system of shooting stars, from the fact that they 
are visible every year with more or less distinctness, and that, as 
an annual shower, they cannot he surpassed by any other display. 
The two celebrated streams of November 13 and 27, occasionally 
giving rise to showers of great splendour, are periodical in 
character, though it is extremely probable that a few of their 
meteors encounter the Earth at the regular return of the dates ; 
notwithstanding that they may elude observation in consequence 
either of moonlight or cloudy weather, which, indeed, generally 
offers some impediment to success. But the August meteors recur 
annually with considerable intensity, and had attracted attention 
at a very remote epoch, though the phenomenon was not sys- 
tematically studied until later times. It was reserved for Heis 
at Aix-la-Chapelle to more thoroughly investigate the meteors 
of August, for the previous observers, though they had ascer- 
tained the fact that the month was notable in this respect, had 
yet neglected to obtain any important data with regard to the 
number or directions of the meteors seen. Schmidt also, at 
Bonn, began assiduously to devote himself to this special line 
of inquiry. The particular night in August when the meteors 
were most plentifully distributed was found to be the 10th, 
though the numbers were subject to considerable variations 
in different years. Schmidt, from an average of several years 
of observations, gave the following as the horary number of 
falling stars for one observer. His results are compared with a 
similar average derived by Major Tupman and the writer from 
observations in 1869-71 and 1877-80 respectively : — 
NEW SERIES, YOU. IV. — NO. XVI. 
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