SOUTH, JAMES. - THE SEVEN-FEET TRANSIT INSTRUMENT DESCRIBED.

On the discordances between the Sun's observed and computed Right Ascensions, as determined at the Blackman-street Observatory, in the years 1821 to 1822; wih Experiments to show that they did not originate in instrumental derangement. Aklso a description of the seven-feet Transit with which the observations were produced, and upon which the experiments were made. Read June 8, 1826.

London, W.Nicol, 1826. 4to. No wrappers as extracted from "Philosophical Transactions" 1826 - Part III. With titlepage to Part III.Pp. 423-482 and 3 engraved plates, of which 2 are larger and folded. A faint dampstain to margins of plates.

James South " fitted up an observatory attached to his house in Blackman Street, Borough, with two equatoreals of respectively five and seven feet focal length, besides a first-rate transit instrument by Troughton Here he observed, jointly with John Frederick William Herschel, 380 double stars. In presenting him with the gold medal of the Astronomical Society in 1826, Francis Baily spoke of his ‘princely collection of instruments, such as have never yet fallen to the lot of a private individual’. In 1835 South removed his five-foot telescope to Passy, near Paris, where he came to know Humboldt and Arago, and convinced Laplace of the reality of revolving stars by ocular demonstration in the case of 70 Ophiuchi. He executed there in a few months what Herschel called ‘a noble series of measures’ on 458 compound stars, of which 160 were new ; and for these labours, together with his paper ‘On the Discordances between the Sun's observed and computed Right Ascensions,’ presented to the Royal Society on 8 June 1826 (the paper offered), was awarded the Copley medal in 1826. He was elected a member of the Royal Society in 1821.

Order-nr.: 46067