Copy letter from Robert William Frederick Harrison, to Messrs Carl Zeiss, 29 Margaret Street, Regent Street, W. 'Gentlemen, The accompanying 2.0.mm Objective has been returned by one of the members of the Sleeping Sickness Commission in Uganda who states that "it has gone wrong in some way". I shall be obliged by your overhauling the lens and returning it to me as soon as possible. I am, faithfully yours, Robt [Robert] Harrison Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 14 February 1906