Copy letter from Robert William Frederick Harrison, to Lieutenant Shackleton, 9 Regent Street, Waterloo Place, W. 'Dear Sir, In response to a request received from a Hydrographer to the Navy, I send you enclosed a spare proof copy of the "Discovery's" Magnetic Observations, into which have been introduced by hand the corrections made in the last proof revised now lying here ready for press. I trust this is what you desire, and remain, very faithfully yours, Robt [Robert] Harrison Assistant Secretary R.S. [Royal Society]' 7 October 1907