Regnault's hygrometer (psychrometer) by Negretti and Zambra, 1 Hatton Garden, London, also marked 2279-I-1866, in fitted wooden case with pair of mercury-in-glass thermometers fitted with brass collars Regnault type hygrometer with mercury thermometer
[Ms. letter] 1871 Jul 9, Royal Commission on Scientific Instruction and the Advancement of Science, 6 Old Palace Yard, London to an unnamed correspondent / J.N. Lockyer. [1p. He writes to arrange a meeting, and to inform his correspondent that he has 'seen the Astr. Royal [G.B. Airy] about another Eclipse Expedtn. & I hope to have authority ... to order Instruments for 3 Stations'. [Lockyer did lead an expedition to Kerala in southern India for the solar eclipse in December of this year] Ms. letter 1871 Jul 9
Spectroscope with camera in aluminium and brass, signed by Hammersley, Islington, London and by W. Ottway and Co., Orion Works, Ealing, with wooden case. Listed as instrument no.23 at the Solar Physics Observatory, South Kensington before being acquired by the Norman Lockyer Observatory, Sidmouth Devon. Spectroscope with camera in aluminium and brass