DISCOVERY OF WOLF'S PERIODIC COMET.—M. Jonckheere, who has been searching for the return of, Wolf's periodic comet since May 4, discovered it on July 9 at 10h. 45m. G.M.T. with the 28-in. equatorial at Greenwich. The comet was at the time of discovery between the 15th and 16th magnitude, and about 9″ in diameter. It is about + 50S. in R.A. and 15′ north of the place given by M. Kamensky's orbit (A.J. 729). On July 10 the magnitude was estimated as 15th, and on July 12 as 14th. The comet was discovered in 1884, when it was of 8th magnitude, and wras observed in the returns of 1891, 1898, and 1911, but not in 1905.