personality, from childhood to old age, but I venture to think we can find portraits which emphasise even the individual moods and characteristic phases of his many-sided mentality. This book may help to preserve that play of expression which forms the charm of our memory of a friend, and which is renewed and kept alive by many photographs, until they perish also.
This perishing of photographic portraits, whether negatives or prints, has been sadly impressed upon me not only -in the case of photographs of Galton himself-which I have endeavoured to put into a more permanent form-but further in the case of nearly all Galton's own photographic work. Box after box of his negatives as well as the prints from them have perished or are rapidly perishing. I felt strongly the need for preserving at least his hitherto unpublished results in composite portraiture. But to add this number of plates to my volume seemed only possible by curtailing its text. This difficulty was finally overcome by the generosity of Mr Edward WhelerGalton and by the aid of one who owed much to Sir Francis. In this way it became feasible to give comprehensive illustration of what Galton achieved in composite photography. The exhibit will, I hope, lead to the renewal of this branch of investigation, for I am convinced that its possibilities are- by no means exhausted.
I have to acknowledge the great aid I have received from my son Mr Egon S. Pearson in dealing with Galton's photographic material and researches. I have further to thank Major Leonard Darwin and my colleague Miss Ethel M. Elderton for aid- in a variety of ways. Lastly I have to place on record a confession. The Galtoniana contain a large number of manuscripts and notebooks in Galton's hand ; many of these are in pencil, much rubbed, occasionally obliterated. In the earlier chapters of this volume I have constantly used this material. Lately I have been unable, owing to failure of sight, to do so. I may well have missed material which ought to have found its place in these pages. My only apology, must be that of what lay in my power to give I have freely given..
UNIVERSITY Co LEoE, LONDON. July 8, 1924.