THE COMPANION TO SIRIUS.—In a letter to the Observatory for April, the Rev. T. E. R. Phillips directs attention to the fact that the companion to Sirius is now readily visible in instruments of moderate aperture. This is accounted for by the circumstance that the companion is now in the neighbourhood of greatest elongation from the bright star. The star was easily observed by Mr,. Phillips with an 8-in. refractor, and it was conspicuously bright in a reflector of 18-in. aperture, but in both cases a quiescent atmosphere was an essential condition. The mean of several determinations gave the position angle of the companion as 72.1°, and the separation as 10.89″. Mr. Innes, of the Union Observatory, Johannesburg, also states that the companion is now an easy object, and for 1917–18 gives the position angle 73.4°, and distance 11.24. The observations suggest that Doberck's period of 49.49 years is too short by 0.22 year, or that the period is 49.71 years.