Copy letter from Herbert Rix, to Messrs Newton & Company, 3 Fleet Street, E.C. 'Dear Sir, Please let some competent person meet Captain [William de Wiveleslie] Abney here at 1 o'clock on Friday to make arrangements about our new lantern which, as you remember, is not yet quite satisfactory. The electricians will also be here, but it probably that some alterations may have to be made in the lenses. We shall in any case be glad to have your attendance. Yours truly, H Rix Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 21 February 1894