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 to the periodic shooting-star showers. In fact, the only common feature which they may be said to possess is that they both come into the atmosphere from the outside. While, therefore, we must admit that such meteor showers as the Leonids are unquestionably connected with comets, yet we must distinctly hesitate to affirm that meteorites have any known relation to these bodies. On this matter Huggins has expressed himself with characteristic caution, though he acknowledged that there is some spectroscopic evidence which might be cited in support of the contention that the nucleus of the comet is not wholly different from the matter which falls down here as meteorites. With reference to the more characteristic features of comets, such as the rapid transformations which they undergo, and the marvellous tails which they shoot forth, the idea seems gradually developing that the phenomena are in the main of an electric character. Sir W. Huggins suggests that the recent discoveries of the electric action of the ultra-violet part of solar light may possibly help to explain the highly electrified condition of comets.

It would not be possible in a résumé of the achievements in modern astronomy to omit an account of the researches on the constitution of the sun made by the late Professor Rowland. He has shown that thirty-six terrestrial elements are certainly indicated in the solar spectrum, while eight others are doubtful. Fifteen elements have not been found though sought for, and ten elements have not yet been compared with the sun's spectrum. Reasons are also given for showing that though fifteen elements had no lines corresponding to those in the solar spectrum, yet there is but little evidence to show