The Philosophy of Birds 3 Nests. 415 



open bamboo floor ; and the whole structure is exceedingly- 

 slight and thin. Now, what can be the reason of this remark- 

 able difference between countries many parts of which are 

 strikingly similar in physical conditions, natural productions, 

 and the state of civilization of their inhabitants ? We appear 

 to have some clue to it in the supposed origin and migrations 

 of their respective populations. The indigenes of tropical 

 America are believed to have immigrated from the north — 

 from a country where the winters are severe, and raised houses 

 with open floors would be hardly habitable. They moved 

 southwards by land along the mountain ranges and uplands, 

 and in an altered climate continued the mode of construction 

 of their forefathers, modified only by the new materials they 

 met with. By minute observations of the Indians of the 

 Amazon Valley, Mr. Bates arrived at the conclusion that they 

 were comparatively recent immigrants from a colder climate. 

 He says : — " No one could live long among the Indians of the 

 Upper Amazon without being struck with their constitutional 

 dislike to the heat. . . . Their skin is hot to the touch, and 

 they perspire little. . . . They are restless and discontented 

 in hot, dry weather, but cheerful on cool days, when the rain 

 is pouring down their naked backs/'' And, after giving many 

 other details, he concludes, " How different all this is with the 

 Negro, the true child of tropical climes ! The impression 

 gradually forced itself on my mind that the Red Indian lives 

 as an immigrant or strauger in these hot regions, and that his 

 constitution was not originally adapted, and has not since 

 become perfectly adapted, to the climate.^ 



The Malay races, on the other hand, are no doubt very 

 ancient inhabitants of the hottest regions, and are particularly 

 addicted to forming their first settlements at the mouths of 

 rivers or creeks, or in land-locked bays and inlets. They are 

 a pre-eminently maritime or semi-aquatic people, to whom a 

 canoe is a necessary of life, and who will never travel by land 

 if they can do so by water. In accordance with these tastes, 

 they have built their houses on posts in the water, after the 

 manner of the lake-dwellers of ancient Europe; and this mode 

 of construction has become so confirmed, that even those tribes 

 who have spread far into the interior, on dry plains and rocky 

 mountains, continue to build in exactly the same manner, and 

 find safety in the height to which they elevate their dwellings 

 above the ground. 



These general characteristics of the abode of savage man 

 will be fbund to be exactly paralleled by the nests of birds. 

 Each species uses the materials it can most readily obtain, and 

 builds in situations most congenial to its habits. The wren, 

 for example, frequenting hedgerows and low thickets, builds 



