Copy letter from Robert William Frederick Harrison, to Professor Dr Paul Ehrlich, Westendstrasse, 62 Frankfurt, Germany Is sending by book post six copies of 'Proceedings of the Royal Society' number 432, from which he will see that his Croonian Lecture is now published. Harrison has given instructions to the Society's printers to press on with the printing of the private copies for Ehrlich and trusts these will arrive very shortly. 24 July 1900