Letter from William [Augustus] Tilden, The Oaks, Northwood, [Middlesex], to The Secretaries, Royal Society Informs he has written a Life of Sir [William] Ramsay, due to be published in early 1918, and that for this purpose wishes to obtain permission for reproducting illustrations of the apparatus used by Lord Rayleigh [John William Strutt] & Professor [William] Ramsay, published in the Philosophical Transactions of the Royal Society. 17 December 1917