Page:Popular Science Monthly Volume 52.djvu/159



HE ethnic history of the British Isles turns upon two significant geographical facts, which have rendered their populations decidedly unique among the other states of western Europe. The first of these is their insular position, midway off the coast between the north and south of the continent. That narrow silver streak between Calais and Dover which has insured the political security and material prosperity of England in later times, has always profoundly affected her racial history. A partial bar against invasion by land, the fatal step once taken, it has immediately become an obstacle in the way of retreat. Invasion thus led inevitably to assimilation. Protected sufficiently against disturbance to assure that homogeneity of type which is attendant upon close contact, the islands at the same time could never suffer from the stagnation which utter isolation implies.