In 1932, London Centre member Donald M. Hennigar built two Newtonian reflectors, a 6″ (15cm) and an 8″ (20cm). Mr. Hennigar showed these telescopes at the RASC London Centre meeting on 1932-11-11, and the telescopes were also set up for a star night at the Higgins’ farm on 1934-09-14. Saturn and Mizar were targets that night.
London Centre members with the Hennigar reflector, 1999-11-25
Mr. Hennigar served as London Centre vice-president in 1936, 1937 and 1938. He and his wife attended many meetings from 1931 until his death in 1951. When Mrs. Hennigar passed away a few years later, the two reflectors and a 4″ (10cm) refractor that he also built were in the hands of their daughter and son-in-law, Mr. and Mrs. Bill Pollard. The Pollards never used the telescopes, but stored them carefully for decades. When Mrs. Pollard, the daughter of D.M. Hennigar, passed away in 1996, Mr. Pollard decided that the telescopes should be given to someone with an interest in astronomy, and found Kirby Alguire, the son of a friend.
Kirby received Mr. Pollard’s blessing to return the 20cm reflector to the RASC London Centre. On 1999-11-25, Kirby visited London and presented the telescope to Centre members. The picture below was taken that night; Kirby is in the front row at the left. The telescope is now part of the RASC London Centre’s arsenal of photon collectors. Meanwhile, the 10cm refractor remains with the descendants of D.M. Hennigar.
Our sincere thanks go to Kirby and Mr. Pollard for bringing this treasure to us!
20cm reflector built by Donald Hennigar
The 20cm telescope looks very similar to the 15cm version, and is shown here as it looked around 1996 after being superficially cleaned. Work still needs to be done to restore the Hennigar reflector to its former glory. Dave McCarter (London Centre President 2000-2010) cleaned the mirror and put it on the Foucault tester. The mirror is 20cm plate glass and nearly f/8. When it came back to us, it showed severe astigmatism and was not well-corrected, with a central depression and a slightly turned edge. The turned edge was almost normal considering the way that mirrors were parabolized at the time. The edge was hidden by the ring mount. Dave McCarter repolished the mirror and parobolized it to about a 1/10th wave. It was recoated in 2000 by Moonward. It would give fine views! London Centre member Dave Rubenhagen reports that the mount, a tapered steel pedestal with an interesting worm gear movement, can be fixed up. The tube is made of rolled sheet metal and can also be rejuvenated. The Hennigar reflector deserves to be maintained and displayed as an example of amateur telescope making in the 1930s.
This is a marvelous piece of the history of the London Centre, and we are thrilled that the tale came back to us. We hope to have more updates in the future