vi Preface 



what (ialton liiul done, and so 8tartiii<j from liis sujjjgestions make a more 

 tliorough map of a district, where (jlaltoii would only chiim to have made a 

 chart of the cartlinal points. In taking this determination I was soon aware 

 that it meant adding a third volume to this />(/<'. I have had to |)ostpone to 

 that volume the discussion of Correlation, the StatistiaU Theory of Heredity, 

 Personal Identification and Description and Eugenics together with many 

 letters, characteristic of Galton's mentality and of his affectionate disposition. 

 But that volume seems an easy one after the present, for it largely deals witli 

 work done after Galton Iwul been recfjgnise<l as a master antl friend. 



The multitude of my own tasks from 1880 onwards gave me little leisure 

 to do more than keep in touch with current work; 1 had small opportunity 

 for considering earlier niemoirs, and many of Galton's papei"s written before 

 I lefl Cambriage I have only read forty yeai^s after their j)ublication. How 

 I now regret that I had not studied them, when with youthful energy still 

 mine I might have pursued further their lines of thought ! How many are 

 the suggestions they make for novel and profitable research! I shall indeed 

 be content, if this book of mine opens up to the younger men of to-day that 

 field of inspiration, which Galton provided for some half-dozen of us in the 

 'eighties. How much one seems to have lost by waiting to explore it fully, 

 until one's ^Vande^'jahre were for ever gone ! 



If this second volume be written essentially to bring the thoughts of a 

 great scientist home to the younger scientists of to-day, to show tiiem the 

 wide regions, practical and theoretical, which Galton opened to the mathe- 

 matician and statistician, there are still some interludes which appeal to a 

 wider audience, such as the beauty of Galton's friendship for Darwin, the 

 interest of his corres}X)ndence with De CandoUe, and his brief contact with 

 the "Passionate Stiitistician." The ingenuity of Galton's mechanisms and 

 the originality of his photographic work will attract others, while in the 

 field of psychok)gy it will be found diflBcult to refute the claim that he was 

 the fii-st English experimentalist. 



If the reader should find Chapter XIII of this work more clumsily 

 worded and carelessly written than those which jirecede it, he will under- 

 stand the loss which the biographer incurred by the death of his friend, 

 W. Paton Ker, while the book was passing through the press. Professor 

 Ker's returned proofs, duly loaded with admonition, ejaculation, and humorous 

 chiding, were not only assumnce that many of the author's blunders were 

 detected, but led him with delight on more than one occasion to unwonted 

 realms, little sought by votaries of science. Let us rejoice that he has lived, 



" And laugh like him to kuow in all our nerves 

 Beauty, the spirit, scattering dust and turves." 



I have again to acknowledge the ready help of Francis Galton's relatives 

 and friends, e.specially in the matter of portraiture. Even as it is 1 have had 

 to make a selection from the vast amount of photograj)hic material placed 

 at my disijosal, and a jX)rtion of that selection is still reserved for the third 

 volume. In contrast to Darwin, Galton was repeatedly photograplu^d, and 

 the result is that we can trace not only the physical changes in his 



