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meteors move are the same as if they were all shot out from this one point, but it must not be supposed that the meteors are actually seen at this point; they may begin to show themselves at any distance from it less than ninety degrees; but when they are seen they are moving from the point. This shows that the meteors are all moving in parallel lines when they encounter our atmosphere. The radiant point is what, in perspective, is called the vanishing point.

The period of the November meteors, thirty-three years, being known, and the exact position of the radiant point determined, it became possible to calculate the orbit of these objects. This was done by Leverrier soon after the shower of 1866. Now it happened that, in December, 1865, a comet appeared which passed its perihelion in January, 1866. Careful study of its motion showed that its period was about thirty-three years. This orbit was computed by Oppolzer, who published it without noticing its resemblance to that of the meteors. Then it was noticed by Schiaparelli that there was an almost perfect resemblance between the orbit of Oppolzer's comet and the Leverrier orbit of the November meteors. So near together were they that no doubt could be felt that the two orbits were identical. The evident fact was that the bodies which produced these November meteors were following the comet in its orbit. It was therefore concluded that these objects had originally formed part of the comet and had gradually separated from it. When a