Copy letter from Robert William Frederick Harrison to Sir Joseph Larmor, MP, FRS 'Your note about offprints puzzled me at first because I did not know what it applied to and because the imprint of reference to the Royal Society Proceedings is upon the wrapper of all authors' copies supplied; but I have come to the conclusion that your note must refer to the obituary notice.of MR John Brown, copies of which I understand were supplied to you without wrappers at your own request. The copies thus escaped the imprint, but to guard against similar accidents in future I will instruct the printers to repeat the reference on the first page of every offiprint.' 31 January 1913