FOR thousands of years man has gradually been fashioning the world of Nature to his own liking, and in the last century lie has made great strides. Now he extirpates whole races of animals (as he has done to the bison and is doing to the whale), razes forests, drains swamps and makes lakes, until the face of Nature is being changed beyond recognition. Side by side with these vast and obvious changes go many as far-reaching. but less obvious, and it is with these, and with their reaction upon man himself, that Professor Tattersall will deal in his series of talks.