66 



ON MAGNITUDE 



[CH. 



with whose dimensions our hves, our hmbs, our senses are in tune. 

 The great whales grow out of this range by throwing the burden 

 of their bulk upon the waiters; the dinosaurs wallowed in the swamp, 

 and the hippopotamus, the sea-elephant and Steller's great sea-cow 

 pass or passed their hves in the rivers or the sea. The things which 



Linear dimensions of organisms, and other objects 



fly are smaller than the things which walk and run ; the flying birds 

 are never as large as the larger mammals, the lesser birds and 

 mammals are much of a muchness, but insects come down a step 

 in the scale and more. The lessening influence of gravity facilitates 

 flight, but makes it less easy to walk and run; first claws, then 

 hooks and suckers and glandular hairs help to secure a foothold, 



