Letter from P [Peter] Chalmers Mitchell, Zoological Society of London, 3 Hanover Square, London, to [Joseph] Larmor He thinks it entirely a matter of arranging the same facts to suit two sets of people, with little but typography separating the two systems [in compiling the Catalogue of Scientific Papers]. He and Professor [Henry Edward] Armstrong could argue on a joint scheme and subscribers would not notice the difference. People on each side would need persuasion. 22 December 1904