Copy letter from Robert William Frederick Harrison, to Sir William Crookes, Fellow of the Royal Society 'Mr Brennan's Exhibit Letter from Mr Brennan enclosed After consultation with Mr Brennan we think it will work better to put this demonstration last instead of first. We can then get the screen and lantern arrangements used for other demonstrations out of the way once for all and leave him a clear field. I shall be glad to have the Chairman's authority for this arrangement. RWFH'. 14 June 1907