PROGRESSION IN OR THROUGH THE AIR. 



155 



sTiould be so. If the flying creature is living, endowed with 

 volition, and capable of directing its own course, it is surely 

 more reasonable to suppose that it transmits to its travelling 

 surfaces the peculiar movements necessary to progression, than 

 that those movements should be the result of impact from 

 fortuitous currents which it has no means of regulating. That 

 the bird, e.g, requires to control the wing, and that the wing 

 requires to be in a condition to obey the behests of the will 

 of the bird, is pretty evident from the fact that most of our 

 domestic fowls can fly for considerable distances when they 

 are young and when their wings are flexible ; whereas when 

 they are old and the wings stiff*, they either do not fly at all 

 or only for short distances, and with great difficulty. This 

 is particularly the case with tame swans. This remark also 

 holds true of the steamer or race-horse duck {Anas Irachy- 

 vtera), the younger specimens of which only are volant. In 

 older birds the wings become too rigid and the bodies too 

 heavy for flight. Who that has watched a sea-mew struggling 

 bravely with the storm, could doubt for an instant that the 

 wings and feathers of the wings are under control 1 The whole 

 bird is an embodiment of animation and power. The intelli- 

 gent active eye, the easy, graceful, oscillation of the head and 

 neck, the folding or partial folding of one or both wings, nay 

 more, the slight tremor or quiver of the individual feathers 

 of parts of the wings so rapid, that only an experienced eye 

 can detect it, all confirm the belief that the living wing has 

 not only the power of directing, controlling, and utilizing 

 natural currents, but of creating and utilizing artificial ones. 

 But for this power, what would enable the bat and bird to 

 rise and fly in a calm, or steer their course in a gale It is 

 erroneous to suppose that anything is left to chance where 

 living organisms are concerned, or that animals endowed with 

 volition and travelling surfaces should be denied the privilege 

 of controlling the movements of those surfaces quite independ- 

 ently of the medium on which they are destined to opeiate. 

 I will never forget the gratification aff*orded me on one occa- 

 sion at Carlow (Ireland) by the flight of a pair of magnificent 

 swans. The birds flew towards and past me, my attention 

 having been roused by a peculiarly loud whistling noise 



