I'Hl-i EMPIRE OF THE AIK. 42cJ 



I'ovoirs ail the types of sailing" iliglit, and produces all the mano^uvers, 

 from that of absolute immobility iu the sky to that of vertical fall; 

 from great velocity to the actual stopping, froiu going forward to going 

 backward; for, from a theoretical standpoint, backward Higiit or back- 

 ward gliding may be considered as feasible. 



VarioiLs niamenvers. — To write concerning the manceuvers performed 

 by soaring birds is somewhat like attemiiting to descrioe a picture 

 or a piece of music in words, — the l)est possible descri]»tion wU) never 

 be worth the roughest sketch, or a line of notes. 



However, as we cannot rest content with always preaching observa- 

 tion to those who can go where the birds are to be found, we shall try 

 to say a few words con(;erning some evolutions of sailing winged crea- 

 tures; for before man dare trusthimself to any apparatus, however well 

 designed, he ought to know, approximately at least, what may be done 

 in the air with such an apparatus, for else he can only be sure of the 

 descent to the ground. 



Birds get their initial start in many ways. For most of them this is 

 tin- easiest act. Those which liavc to vancpiish the greatest ditticulties 

 are the large water birds, which in starting from water or ground are 

 com])elled to run a long distance, using both feet and wings, in order 

 to gain the si)eed re([uired for su])port. This applies to large sea birds 

 with narrow w4ngs, and in general to all water birds: such as the geese, 

 the swans, the ])elicans, etc. 



The rowing birds simply juni]) into the air to take flight; their ])ec- 

 toral nuiscles are so ])owerful that they enable them to get sup])()rt 

 without much headway; moreover this lea]) possesses great energy; 

 this may be realized by watching the leaps of a large passerine bird 

 deprived of his wing feathers, such as a raven or a magi)ie: one single 

 lea]) sends them u]) three feet. 



The smaller the bird the greater is this initial leai> in i»roi)()rtion; as 

 Avitness the blackbird, the lark, and that lile-spark, th<^ tomtit. Among 

 the birds, the stiength of the legs follo\\'s the saine law as that of the 

 pectoral mu.scles; it increases in ])ro])ortion as the weigiit diminishes. 

 In fact, a niglitiiigale or a sylvia use their wings when iu a thicket 

 only as an aid to (equilibrium and as directing power. 



The i)lovers, certain scolojtax, the tringas, etc., get into flight by ]>r<>- 

 vious running. The larger number of the great wachMs, the larg<' vul- 

 tures, etc., also get their start by running, if on the gionnd, but as 

 soon as they can, they al)an(h)n the running steps for a- scries oC leaps 

 whi(;li continue as long as their teet can touch the ground. 



lUids of ]»rey in general ha\'e two methods of glutting under way. 

 When they start tVom the ground, with or without a |)rey (excej^l vul- 

 tures), they always enter into action by a lea]) measuring a yard. 

 When they are on the i)eich, being always at great heights, the\' sim 

 l»ly launch into s]»a<'e and sjtread their wings o])e!i to get under full 

 motion. 



