22 INTRODUCTION. 



the opinion, written in English, of Christian Gaika, 

 brother of the Chief Sandilli, on the expressions of his 

 fellow-countrymen. In the northern regions of Africa 

 Captain Speedy, who long resided with the Abyssinians, 

 answered my queries partly from memory and partly 

 from observations made on the son of King Theodore, 

 who was then under his charge. Professor and Mrs. 

 Asa Gray attended to some points in the expressions of 

 the natives, as observed by them whilst ascending the 

 Nile. 



On the great American continent Mr. Bridges, a 

 catechist residing with the Fuegians, answered some 

 few questions about their expression, addressed to him 

 many years ago. In the northern half of the conti- 

 nent Dr. Rothrock attended to the expressions of the 

 wild Atnah and Espyox tribes on the Nasse Eiver, in 

 North- Western America. Mr. Washington Matthews, 

 Assistant-Surgeon in the United States Army, also ob- 

 served with special care (after having seen my queries, 

 as printed in the ' Smithsonian Eeport ') some of the 

 wildest tribes in the Western parts of the United States, 

 namely, the Tetons, Grosventres, Mandans, and Assina- 

 boines; and his answers have proved of the highest 

 value. 



Lastly, besides these special sources of information, I 

 have collected some few facts incidentally given in books 

 of travels. 



As I shall often have to refer, more especially in the 

 latter part of this volume, to the muscles of the human 

 face, I have had a diagram (fig. 1) copied and reduced 

 from Sir C. Bell's work, and two others, with more ac- 

 curate details (figs. 2 and 3), from Henle's well-known 

 'Handbuch der Systematischen Anatomie des Menschen.' 

 The same letters refer to the same muscles in all three 



