THE EMl'IKE OF THi: AlK. 451 



rile Wiitl who sjnt-ads liis luiiiiaiv rcaliM'r> most widely ai»ai't tVoiii 

 eacli other. Tlune is ;{i, the i'Xtieiiiity an open sjtace between eacli 

 (juill about live tiims the widtli oi" the featlier. 



Still anotlier ix'culiarity: th<' primary Teatlieis, instead of taperini^' 

 towards the i»oiii1. are I'onslriieted on the re\'erse i)lan ; tliey se<'ni to 

 be implanted into the wini^' l»y the tlnn end; the onter tip being' mate- 

 rially wider than the i)arl whieli seems to l)e attached to the wing, and 

 wliieh prececU^s the main widening of the barbs. Thes<' hirge feathers, 

 widest at their tip and s])read asnnder. ])resent a curious outline which 

 would ])Iease artists greatly i1 tliey could observe this bird in his 

 native habitat. 



To the ])eeuliar construction described wennist add theeffetds of the 

 paitial rotation of the quills within their sockets, which action is ob- 

 served only in these large birds. These quills uinst be wonderfully 

 strong and elastic, for the birds put them to sev(n'e proofs. During 

 the efforts winch he nnikes when starting nj) from the ground and when 

 his pectoral mnscles are doing their ntmost. the tips of the feather 

 point directly to the zenith. Tn short, from every point of view these 

 great birds, when free, are exceedingly interesting to observe. There 

 are altitudes, (ptite unknown to those who only see the bir<l in museums, 

 which would confer success on an animal painter, il' he reproduced 

 them. 



But there nuist be freedom; otherwise, we have only eagles motion- 

 less as milestones, or ill-smelling \ultures worrying themselves to 

 death, tlieir Iseads smothered between their shoulders: tw(» aspects 

 which have nothing in comnnm with that of these kings of air ])roudIy 

 traversing the immensit,> of the skies. The one circumstam-e Mhich 

 frequently deprives tin* observer of the chan<'(^ of witnessing their in- 

 teresting evolutions is the bird's alarm. At the slightest apprehen- 

 sion these great creatures resort to rowing Hight, they desire to get 

 rapidly beyond dang<H'. so tlnit de\('loi)ing all their powers with strokes 

 of wing they (pnckly Hy away. 



Their ])ower of vision must be great ; we may safely assume this, 

 because these birds, of all flying creatures, are those whose mode of life 

 requires the most extensive views. 



A sparrow ihhhIs a tield ol" \ie\\ ol' but a l\-\\ hundred yards: a more 

 powerful organ of sight would be needless, and therefore atro))hied in 

 a few generations; the sea birds need to obserse the surface of the 

 w-aves for only some dozen yards or so. It is not among' these creatures 

 that we nnist seek Ibi' those ])ertect lenses. cai)able of collecting all 

 divergent I'ays of light. 



The hunting biids of prey, such for instance as the falcons and the 

 eagles, often scrutini/.e the surface of the grouiul from a great height; 

 the latter birds, especially-, sometimes maintain themselves at an ele- 

 vation of 4()(» or o(Kj vards while hunting; but what is that distance 



