Prefatory Note 



In the preparation of this book there have been 

 large drafts from the materials supplied by Mr. 

 Leonard Huxley in the very admirable Life and 

 Letters of his father. The foot-note references to 

 that work are sufficiently denoted by the omission 

 of its title. 



For the convenience of readers who may not 

 possess the original editions of Huxley's writings, 

 the references to them are, for the most part, cited 

 from the Collected Essays, 



