fairly be said that the theory which now associates meteors and comets in the most unmistakable manner was suggested by one accident and confirmed by another. Albeit such accidents happen only to the zealous student of nature's secrets. We shall presently see that the fortunate detection of Tempel's comet in 1866 was not the last of the series of coincidences by which the theory of meteors was established. Although the evidence favouring Schiaparelli's theory was now strong, yet it was well that at this stage still more convincing evidence was forthcoming. The date of the November display has changed since the Leonides were first recognised, in such sort as to show that the position of their path has changed. The change is due to the disturbing attractions of the planets. It occurred to our great astronomer Adams, discoverer with Leverrier of distant Neptune, to inquire whether the observed change accorded with the calculated effects of planetary attraction, if the Leonides are supposed to travel in any of the smaller paths suggested by astronomers, or could be explained only by the assumption that the meteors travel on the widely-extending path corresponding to the 33-1/4 years period. The problem was worthy of his powers--in other words, it was a problem of exceeding difficulty. By solving it, Adams made that certain which Schiaparelli and his followers had merely assumed. He showed beyond all possibility of doubt or question that of all the paths by which the periodic meteoric displays could be accounted for, the wide path carrying the November meteors far beyond the track of Uranus was the only one which accorded with the observed effects of planetary perturbation.