A.A.C.E. Merlin’s observatory

Ealing, London

Journal of the British Astronomical Association, 53 (4/5), 162, June 1943

The two main instruments are a 12¼-inch With reflector and an 8½-inch Horne and Thornthwaite reflector – the former equatorially mounted and clock-driven, the latter on an altazimuth mount with slow motions. The 12¼-inch With, of 6 feet focus, carries (in addition to a 2¼-inch finder) a 5-inch ‘comet finder’ refractor of 25 inches focus, provided with a stainless steel diagonal eyepiece for convenience in observation. The 12¼-inch is also provided with electrically illuminated dark and bright field bifilar position micrometers. A clock-driven equatorially mounted 3.3-inch Wray refractor, and a 3¼-inch Gifford–Hilger apochromatic refractor, are also in use. Planetary and other observational work has been carried on at Ealing during the past twenty-three years. Previously, work was carried on for very many years with the 8½-inch reflector at Volo, Thessaly, where the instrument was housed on the paved roof of the British Consulate. The practical advantages of this former position have proved very marked in comparison with the garden ground-level observatory at Ealing, where trees and houses greatly impede the view of low down celestial objects. A small but good transit instrument was also mounted on the roof of the Volo Consulate. This for many years served to regulate the town clock in days before the advent of wireless time-signals. Rainfall and Stevenson screened thermometer readings were also regularly recorded at Volo, and have been continued up to the present at Ealing. Particulars of observational work done both at Volo and Ealing have been published in English Mechanic under the heading of ‘Fifty Years at the Telescope’. These communications are too numerous and varied to

be here touched upon. It may be mentioned, however, that one interesting object the 12¼-inch served to reveal at Ealing was Saturn’s satellite Mimas during the last disappearance of that planet’s ring system when placed edgeways towards the Earth. This weirdly dim speck was twice seen and steadily held, with averted vision – once at the east elongation of the satellite and once at the west elongation – under a power of 600 diameters.

Eliot Merlin died in 1947, and the 12¼-inch and 8½-inch reflectors, the transit instrument, and several other instruments, were presented to the Association by Mrs Merlin in 1948.