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In the former paper, read in December 1862, the author had detailed the points of interest that had been found in discussing the angles of position, distances, and magnitudes of certain double stars which he observed at Elchies with Mr Grant's fine telescope in last September; and he now treated similarly the observations of the colours of the stars then and there observed. The chief point to notice being, that in certain cases the colours undergo periodical variations; with the star “95 Herculis” in twelve years, almost exactly within the tenth part of a year, if older records can be trusted to implicitly; and such periodical change the author considered a new feature in this branch of astronomy, and one of a most important and hopeful character for observers to follow up in future.