CONTENTS. 



CHAPTER I. 



PAG 



INTRODUCTORY 1 



CHAPTER II. 



EXPRESSION. 



The term "expression" explained Speech expressive of 

 life ; speech a criterion of life The uniform coexistence 

 of two phenomena makes the one an expression of the 

 other Abstract properties, and their objective signs ; 

 criteria of mind Comparison of an idiot, and an intelligent 

 man Certain sounds and a tracing of the pulse express 

 the action of the heart Signs due to an afferent force ; 

 action of the sight of an object upon children ; a ther- 

 mometer indicates heat; the sensitive flame The tele- 

 phone exhibits impressionability; a receptive part, an 

 expressive part, and an additional force thrown in The 

 phonograph exhibits localized impressionability, which 

 is permanent Impressionability and retentiveness in 

 a child Expression, direct and empirical Impression- 

 ability and retentiveness Nutrition; its signs Move- 

 ments in plants ; by pulvini, by unequal growth Expres- 

 sion by form, colour, temperature Vital processes can 

 only be studied by their expression ; the importance of 

 appreciating this in biological work Summary 11 



