Copy letter from Herbert Rix, to the Rev Stephen Joseph Perry, Fellow of the Royal Society 'Dear Sir, The plate by Capt [Captain] Masterman is in the hands of the lithographers, but the Secretaries think that Mr Osburn's diagram might be done on wood, which would be much cheaper. I shall be glad, however, to know whether you approve of this, & if so whether you prefer to have it done white on black or black on white. We propose to engrave it 2/3rd size. I am yours faithfully Herbert Rix Asst Sec RS [Assistant Secretary, Royal Society]'. [July 1889]