Copy letter from Herbert Rix, to Professor Charles Piazzi Smyth, [Fellow of the Royal Society] 'Dear Sir, The album of photos. [photographs] of the solar spectrum, recently sent by you for the Govt [Government] Grant Committee to inspect, appears to be a very suitable thing for exhibition at our forthcoming Soirée. I write to ask whether we may put the album out on that occasion, & enter it in the programme as exhibited by you? Yours truly Herbert Rix Asst Sec RS [Assistant Secretary, Royal Society]'. 10 April 1891