Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society to Professor Ernest William MacBride FRS 'With a view to save expense we are proposing to reproduce the coloured figures illustrating your paper on the stick insect by 3-colour process, but should like your approval before actually putting the work in hand. We could employ a firm who has done more or less similar work for us (See e.g. Proc[eedings[ B Vol 87, p1 11). 3 colour process is very accurate, though not always so delicate as high class lithography, but in view of the great economy (say 50%) it seems advisable to use it whenever possible, especially at such a time as the present.' 23 July 1915