INTK OD UCT1ON. 



philosopher, he may even discover the inflammable and lighter 

 gas by which a balloon ascends, with the weight of a man 

 attached ; but how shall he lift a substance heavier than the 

 air 1 And how guide its progress through the air 1 Show him 

 the weighty body of an eagle or a swan,* tell him their living 

 history, and he may reasonably doubt your fact, and deny that 

 these things could be. 



There is one difficulty in the use of wings that any one may 

 ascertain for himself. Let him take the smallest sized boy's 

 kite by the narrow end, and wave it up and down at arm's 

 length ; he will instantly perceive how great is the resistance 

 of the air, and how obvious the inability of his muscular 

 strength to produce anything like the rapid motion of a wing. 

 And yet, in order to possess the powers of a bird, he must be 

 able to construct and move artificial wings, in superficial extent, 

 in some cases measuring several of such kites, with the addi- 

 tional difficulties, which mathematical knowledge would prove 

 to be proportionally increased at every step in his progress. 

 How all these seeming impossibilities are accomplished is 

 perhaps the most interesting part of the following pages. 



But the study of Ornithology has other charms, in a great 

 measure confined to itself, and recommending it to the attention 

 of a large class of readers ; namely, that of its being within 

 the reach of all who take an interest in the proceedings of the 

 natural world. Quadrupeds, generally speaking, are few in 

 number, and so difficult of access, that in fact, beyond the 

 limited families of our domestic menageries, few can have an 

 opportunity of investigating their habits. Out of eighty 

 genera of four-footed animals, about fifteen only are to be met 

 with in the British Islands ; of these many live so remote from 

 man, that accident alone can gratify his curiosity, and of that 

 greater portion scattered over the earth, few, comparatively 

 speaking, ever fall under the observation of the most inquiring 

 traveller. One-half of the characteristic features of the lion 

 and tiger tribe we collect from the analogous habits of one of 

 a similar genus, namely, the cat, which harmlessly purrs by OUT 

 * The wild swan weighs 25 Ibs. 



