MAN. 361 



til climates -man everywhere becomes most essentially asso- 

 ciated with terrestrial life. It is by these relations that the 

 obscure and much contested problem of the possibility of one 

 common descent, enters into the sphere embraced by a general 

 physical cosmography. The investigation of this problem will 

 impart a nobler and, if I may so express myself, more purely 

 human interest to the closing pages of this section of my work. 



The vast domain of language, in whose varied structure we 

 see mysteriously reflected the destinies of nations, is most 

 intimately associated with the affinity of races; and what 

 even slight differences of races may effect, is strikingly mani- 

 fested in the history of the Hellenic nations in the zenith of 

 their intellectual cultivation. The most important questions 

 of the civilisation of mankind, are connected with the ideas of 

 races, community of language, and adherence to one original 

 direction of the intellectual and moral faculties. 



As long as attention was directed solely to the extremes in 

 varieties of colour and of form, and to the vividness of the 

 first impression of the senses, the observer was naturally dis- 

 posed to regard races rather as originally different species 

 than as mere varieties. The permanence of certain types* in 

 the midst of the most hostile influences, especially of climate, 

 appeared to favour such a view, notwithstanding the shortness 

 of the interval of time from which the historical evidence was 

 derived. In my opinion, how r ever, more powerful reasons can 

 be advanced in support of the theory of the unity of the 

 human race, as, for instance, in the many intermediate grada- 



* Tacitus, in his speculations on the inhabitants of Britain, (Agricola, 

 cap. ii.,) distinguishes with much judgment between that which may be 

 owing to the local climatic relations, and that which, in the immigrating 

 races, may be owing to the unchangeable influence of a hereditary and 

 transmitted type. " Britanniam qui mortales initio coluerunt, indigen* 

 an advecti, ut inter barbaros, parum compertum. Habitus corporis 

 varii, atque ex eo argumenta ; namque rutilae Caledoniam habitantium 

 comae, magni artus Germanicam originem adseverant. Silurum coiorati 

 vultus et torti plerumque crines, et posita contra Hispania, Iberoa 

 veteres trajecisse, easque cedes occupasse fidem faciunt : proximi Gallis, 

 et similes sunt : seu durante originis vi ; seu procurrentibus in diversa 

 terris, positio coeli corporibus habitum dedit." Regarding the persistency 

 of types of conformation, in the hot and cold regions of the earth, and 

 in the mountainous districts of the New Continent, see my Relatiait 

 \utorique, L i. pp. 498, 503, and t. ii. DD. 572. 574. 



