A 'Digges Telescope'

From Mr Colin Ronan and Mr Gilbert Satterthwaite

We understand that some members are interested in having details of the optical parameters of the 'Digges telescope' displayed on the 1992 August 16 transmission of The Sky at Night. We therefore present a diagram. Readers may also care to note that a similar instrument has been constructed at Leicester University since the broadcast. Like that of the instrument made by us, its field of view is very small, and confirms the remarks made by William Bourne, and quoted in the Presidential Address given in October 1991. [1]

[1] Ronan, C., J. Br. Astron. Assoc., 102, 339 (1191)