Autograph Letter Signed, explaining that Sir John Lubbock is obliged to defer his visit to Cragside “for his explorations with you”. 2 pp. 8 x 5 inches, one corner torn away (without loss of text), otherwise good. Newcastle upon Tyne, 27 November 1866. Sir William George Armstrong (1810-1900), inventor, known for the development of the Armstrong Gun, founder of the Armstrong Whitworth empire.