er a still greater group called by astronomers the
Leonids. The Leonids revolve round the Sun in a period of 33 years, and
in an elliptic orbit, one focus of which is about at the same distance
from the Sun as we are, the other at about that of Uranus. The shoal of
stars is enormous; its diameter cannot be less than 100,000 miles, and
its length many hundreds of thousands. There are, indeed, stragglers
scattered over the whole orbit, with some of which we come in contact
every year, but we pass through the main body three times in a
century--last in 1866--capturing millions on each occasion. One of these
has been graphically described by Humboldt:

"From half after two in the morning the most extraordinary luminary
meteors were seen in the direction of the east. M. Bonpland, who had
risen to enjoy the freshness of the air, perceived them first. Thousands
of bodies and falling stars succeeded each other during the space of
four hours. Their direction was very regular from north to south. They
filled a space in the sky extending from due east 30 deg. to north and
south. In an amplitude of 60 deg. the meteors were seen to rise above the
horizon at east-north-east, and at east, to describe arcs more or less
extended, and to fall towards the south, after having followed the
direction of the meridian. Some of them attained a height of 40 deg., and
all exceeded 25 deg. or 30 deg.. No trace of clouds was to be seen. M. Bonpland
states that, from the first appearance of the phenomenon, there was not
in the firmament a space equal in extent to three diameters of the moon
which was not filled every instant with bolides and falling stars. The
first were fewer in number, but as they were of different sizes it was
impossible to fix the limit between these two classes of phenomena. All
these meteors left luminous traces from five to ten degrees in length,
as often happens in the equinoctial regions. The phosphorescence of
these traces, or luminous bands, lasted seven or eight seconds. Many of
the falling stars had a very distinct nucleus, as large as the disc of
Jupiter, from which darted sparks of vivid light. The bodies seemed to
burst as by explosion; but the largest, those from 1 deg. to 1 deg. 15' in
diameter, disappeared without scintillation, leaving behind them
phosphorescent bands (trabes), exceeding in breadth fifteen or twenty
minutes. The light of these meteors was white, and not reddish, which
must doubtless be attributed