Further information on the telescopes of Hindley of York

Abstract

Since the preparation of my paper on the two equatorial mounting telescopes made by Henry Hindley (1701-1771), published in the previous issue of Notes and Records (1), one of his two instruments has been located and identified. As this York instrument and clock-maker is only known to have made two telescopes, both of an advanced type, the finding of such an instrument is of considerable significance. It is to be found in the Science Museum, South Kensington, and was jointly recognized by Mr R. J. Law on the Museum staff in the company of the writer. Its maker had been presumed to be one John King of Bristol, whose name appears engraved in the compass box which lies within the base tripod. However, since John King is unknown as an instrument maker, the question of whether he actually made the telescope was raised in 1948 when it was acquired by the Museum. The telescope is almost certainly the one that John Smeaton (1724-1792, F.R.S. 11753) described as being made for the Duke of Norfolk about the year 1762, more than twenty years after the first instrument as seen by Smeaton on his visit to Hindley’s York workshops in 1741 (2). On the accompanying photograph, the bell-shaped balance beneath the equatorial plate can be clearly seen. This counterbalance was incorporated by Hindley on the suggestion of Smeaton (2) to overcome the flexing of the mounting. The balance was clearly designed as an intergal part of the mounting unlike the arc-segment applied to the telescope described in the previous issue; the latter’s mounting had had to be modified and pillars introduced to accommodate the balance.