20 FIRST TEAR SCIENCE 



eluded and unprogressive peoples are still to be found. 

 Such are the Highlanders of Scotland and of our own Ap- 

 palachian plateau. The gentler inequalities of the earth's 

 surface have by their lakes and rivers afforded easy means 

 of transportation from one community to another and have 

 opened paths into hitherto unexplored regions. These 

 waterways have been from the earliest times arteries of 



A COTTAGE IN THE SCOTCH HIGHLANDS. 



commerce and progress, and largely through them have 

 the interior lands been colonized and developed. 



Where great plains and plateaus stretch their broad and 

 level surfaces over vast areas, plants, animals, and men for 

 ages, unimpeded by natural barriers, have been thrown to- 

 gether and have striven unrelentingly for mastery. They 

 have here developed into great aggregations, not into small 

 distinct communities. Here there has been no shelter for 

 the weaker group except as its identity was lost in merg- 

 ing with the mass. 



