PREFACE. iii 



Several photographs of Balfour, taken at different 

 times of his life, the last shortly before his death, are in 

 the possession of his relatives and friends ; but these, in 

 the opinion of many, leave much to be desired. 



There 'is also a portrait of him in oils painted since 

 his death by Mr John Collier, A.R.A., and Herr Hilde- 

 brand of Florence has executed a posthumous bust in 

 bronze*. The portrait which forms the frontispiece of 

 Vol. i. has been drawn on stone by Mr E. Wilson of 

 the Cambridge Scientific Instrument Company, after the 

 latest photograph. Should it fail, in the eyes of those 

 who knew Balfour well, to have reproduced with com- 

 plete success his features and expression, we would ven- 

 ture to ask them to bear in mind the acknowledged 

 difficulties of posthumous portraiture. 



* In possession of the family. Copies also exist in the Library of 

 Trinity College, and in the Morphological Laboratory, at Cambridge. 



