THE KMI'IKE OF TJU: AJli. 415 



To ineusuie acc-ui-ately the speed of traiishition of the bird, \\v can- 

 not survey liim in tlie air, for we have no reference points. It is to 

 the bird's sliadow npon the ground that we niust direct our attention. 

 This shadow is easily foHowcd by the eye; it may be g'auged by the 

 speed of a liorsc. of a chance (hinkey, a dog', a carriage, or a railway 

 train : ami t has w c get suie data and trustworthy points of comparison. 

 For instructive observation it is well to study nniny models, ami to 

 live close to them. 



For instance, as i write these lines two families of domesticatc(l 

 raVens are within a few yards, awaiting for the food I am about to 

 throw to them. On the mosque, in front, my ])et kites are perched, 

 waiting my appearance to phmge toAvards me, at the least gesture I 

 may simulate of casting meat to them. Thus I can closely view this 

 expert at full si)eed, for there are two of them which snatch their ])it- 

 tance from my baud. 



There are endless battles between ravens and kites and among kites 

 themselves, and battle always brings the i)erformauce of feats; con- 

 stantly does the kite turn over back downward, this being a favorite 

 fighting ]>osture with all the eagle tribe. I often see two kites lock 

 claws u\) in the air, clutched fast, and thus locked spin down hun- 

 dreds of yards. 



When a great wind blows, the observation is wonderfidly interesting. 

 To try to explain these complicated movements with mathematical 

 formula; seems a farce. Their mere description is difficult enough; 

 how then can we fasten within algebra's rigid rules the evolutions, the 

 feats, the stratagems, which shift with each wind gust, with each 

 fancy! It is like an attemj)t to calculate the foot pounds expended by 

 a gymnast during his exercises, or the thermal units utilized inastrng- 

 gle between two athletes. 



What is most knc^wu concerning the speed of birds is generally 

 vague, for they do not lend themselves to accurate experiment. The 

 speed of flapping flight is pretty well indicated by the carrier pigeons, 

 who, by a dead calm, cover from 33 to •")(► miles an honi'. according to 

 si)ecies. 



We know that the turtledove flies taster than the \\()od-i>igeon. its 

 \<'locity being about .")() miles an hour. Ducks and teals have greater 

 sw iftiu'Ss still, but it is dillicult to determine how mnch. jMoreovei-, 

 the effective speed is governed by the force and direction of the wind. 

 It is ther(-for<; almost imjtossible to be exa('t as to the s])eed of liapping 

 birds, and the ((uestion j>ossesses snuill interest for liim who thinks 

 the soaring birds to be the tru<5 model to imitate. 



The sailing birds affoid an occasional chance of nu'asuring tlu'ir 

 speed of flight, which naturally varies with the wind, bnt which always 

 illustrates the advantage of nniss. There often is a race IxMwceii llii'e(^ 

 birds of diffei-ent si/e: the tawny vultnr<', the l\g.\i>tian \iiltiin'. an(| 

 the kite. 



