Copy letter from Herbert Rix, to Professor Alexander Stewart Herschel, Fellow of the Royal Society 'The Soirée Committee have accepted your spectrum map without seeing it, as it was thought certain to be of interest. So we shall be glad to have the title for the programme at your early convenience. Yours truly, H. Rix Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 8 June 1892