their orbit with that of the earth every November 13th; but later
investigators found that the real period was about thirty-three and
one-quarter years, so that the great displays were due three times in
a century, and their return was confidently predicted for the year
1866. The appearance of the meteors in 1832, a year before the great
display, was ascribed to the great length of the stream which they
formed in space -- so great that they required more than two years to
cross the earth's orbit. In 1832 the earth had encountered a
relatively rare part of the stream, but in 1833, on returning to the
crossing-place, it found there the richest part of the stream pouring
across its orbit. This explanation also proved to be correct, and the
predicted return in 1866 was duly witnessed, although the display was
much less brilliant than in 1833. It was followed by another in 1867.

In the mean time Olmsted's idea of a cometary relationship of the
meteors was demonstrated to be correct by the researches of
Schiaparelli and others, who showed that not only the November
meteors, but those of August, which are seen more or less abundantly
every year, traveled in the tracks of well-known comets, and had
undoubtedly an identical origin with those comets. In other words the
comets and the meteor-swarms were both remnants of original masses
which had probably been split up by the action of the sun, or of some
planet to which they had made close approaches. The annual periodicity
of the August meteors was ascribed to the fact that the separation had
taken place so long ago that the meteors had become distributed all
around the orbit, in consequence of which the earth encountered some
of them every year when it arrived at the crossing-point. Then
Leverrier showed that the original comet associated with the November
meteors was probably brought into the system by the influence of the
planet Uranus in the year 126 of the Christian era. Afterward