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    THE OBSERVATORY OF HARVARD COLLEGE, U.S.—The Annual Report of the proceedings of this Observatory, presented to the visiting Committee in November last by the present zealous director, Prof. Pickering, has been issued. Aided by the subscription raised in 1878 for the support of the Observatory for five years, the director has been enabled to keep the establishment in great activity, and his Report will be a gratifying proof that the funds placed so liberally by subscribers at his disposal are being dispensed in a manner that must prove of great advantage to the progress of astronomical research. Three instruments the equatorial of 15-inches aperture, the meridian circle, and the meridian photometer, have been kept in active work. With the former, sixty-four eclipses of Jupiter's satellites were observed photometrically, an improvement having been introduced by which the number of settings is largely increased. A single observer, it was found, could make but three settings in a minute, or one in twenty seconds. With an assistant to record, the time is reduced to about nine seconds, while by the employment of two assistants, one of whom reads the photometer circle, while the other records and observes the time by the chronometer, the time is reduced to fire seconds. It is probable that, as the observer does not remove his eye from the eyepiece, the accuracy of the observations is increased, and the satellite followed nearer to the point of disappearance. The search for objects having singular spectra, which only admits of being carried on in perfectly clear, moonless nights, had been much interrupted by other current work. The most notable result was the discovery of the peculiar spectrum of the star Lalande 13412, a seventh magnitude; two of the lines appear to be coincident with two in the spectrum of the great comet of 1881, as described by Dr. Konkoly; “accordingly, while other comets have a spectrum identical with that of the stars of Secchi's fourth type, this comet contains a substance as yet unknown, which one star only is as yet known to contain.” The star L2 Puppis was found to have a banded spectrum; its declination is more than forty-four degrees south of the equator, and at the time of Prof. Pickering's examination it was less than two degrees above the horizon. Its variability was pointed out by Dr. Gould (Uranometria Argentina, p. 279); he inferred a period of about 135 days; maxima occurred in 1874 on Feb. 8 and June 25; the star is stated to be red in all its stages and remarkably so about minimum, limits of variation 3.6 and 6.3. The position for 1875.5 is in R.A. 7h. 9m. 43s., N.P.D. 134° 26′.2. The spectra of all the stars north of - 40°, marked as red or coloured in Dr. Gouldapos;s work have been examined at Harvard College, no peculiarity of spectrum being detected in the majority. Algol and the star D. M. 81°, 25 were assiduously studied photometrically. The meridian-circle had been in use on 250 days. The work originally proposed for the meridian-photometer, viz., the measuring on three nights the light of each of the naked eye stars visible in the latitude of the Observatory, was essentially completed on August 25, 1881, but it is intended to continue the observations for another year, as the necessary delay in reduction and publication will not be greatly increased thereby. With the view to a more complete comparison of the photometric observations with those made by the naked eye, which the Uranometria Argentina affords the means of doing as far as 10° north, all the stars in the Atlas Cælestis Novus of Heis north of the equator and brighter than the sixth magnitude, are being measured by the eye, aided by an opera-glass when necessary. It is intended that each star shall be measured by three observers, who are to compare it with two stars in the vicinity of the pole, one a little brighter, the other a little fainter; the interval between the two stars is supposed to be divided into ten parts, and the brightness of the star under comparison is estimated on terms of this interval. Prof. Pickering mentions that out of about nine thousand comparisons required for this work, nearly a quarter have been already made.

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