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Observatory Work.

The shower of Leonids Friday night was considerably smaller and less satisfactory than that of the preceding evening. In all one hundred and forty-seven meteors were observed in the course of the evening at the Harvard Observatory of which eighty-three were Leonids. The shower did not commence until after 12 and was at its height between 2 and 3 o'clock. From the reports of Pacific coast observatories it appears that the main shower was visible only in the west, due to the fact that the earlier daylight in the east made the Leonids invisible during the larger showers.

On Saturday and Sunday evenings no Leonids were observed and it is thought that the shower is past for the present year. The shower this year is probably the last for thirty-three years, although it is possible that next year a small shower may be visible. The color of the Leonids was a faint green. Three dozen photographs were taken during the night, but they were not very successful, as the Leonids were much fainter and of shorter duration than on the preceding evening. In all about seven dozen photographs were made and although they have not as yet been carefully examined their development shows them to have been fairly successful. The Observatory succeeded in getting several photographs of the Leonids' trails and by the use of them will probably be able to locate the radiant. Two plates seem to show photographs of the spectra of the Leonids. This is an unusual success, as it is very difficult to photograph the spectrum of a falling body. It cannot be stated positively that photographs of spectra have been obtained until a more careful examination has been made.

A circular was issued Saturday by Professor E. C. Pickering, in which he announces the first successes ever made in photographing the spectrum of a lightning flash. Comparison of the three negatives obtained at different times in the months of July and September shows the curious fact that the spectrum of lightning is not always the same. The spectrum of the flash closely resembles that of the new star, the Nova Persei. The apparatus was the same as is used in obtaining photographs of the spectra of stars and the success of the experiment, it is expected, will open a new field for spectroscopic work.

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