402 THE EMPIRE OF THE AlK. 



ot nature, by takiug accouutand thought of the various movements, 

 operations, and evolutions of tlie birds, by becoming acquainted with 

 all their niananivers, and above all by understanding them correctly, 

 the how and the wherefore. Witliout all this information success is 

 not possible. If the man does not clearly understand what the bird 

 does and intends in a given position and a certain conjuncture, how 

 can he hoiieto imitate its flight "? 



The observer must constantly set problems for himself, in the hope 

 that occasionally the bird will demonstrate a solution. Thus, I was 

 convinced, a priori^ that an expert soarer could, in a fresh breeze, 

 rise directly into the air and advance against the wind at the same 

 time. I felt sure that the feat was feasible. 1 waited for years before 

 witnessing this evolution. At last one day in Africa, two eagles in 

 love afforded me this spe<'tacle. One of them launched from the top 

 of the ash tree which served as a perch, descended against the wind 

 6-to 10 feet, was raised up by a gust of wind, and thus continued to 

 rise, slowly, steadily, for a hundred yards into the air, while he also 

 advanced some 50 yards against the wind, without a single beat or im- 

 j)ulse of his mighty wings. 



Such convincing demonstrations are not to be seen every day; they 

 must be persistently awaited ; the observer must burn with the sacred 

 tire; he must be drawn to the study of flying creatures by that unde- 

 finable enthusiasm which shall cause his heart to throb when he wit- 

 nesses certain evolutions. - - - 



It is but rarely that a bird manteuvei' is absolutely incomprehen 

 sible; for peculiarities and motives not understood upon a tirst demon- 

 stration are explained by fresh observations made under happier condi- 

 tions. In all cases, to learn the how and wherefore, the study must 

 be a labor of love. 



All my life shall I remember the tirst flight which I saw of the Gyps 

 fidvKs, the great tawny vultures of Africa. I was so impressed that all 

 day long I could tliink of nothing else; and indeed there was good 

 cause, for it was a i)raA'tical, ])erfect demonstration of all my precon- 

 ceived theories coucerniiig the possibilities of artiftcial flight in a wind. 

 Since then I have observed thousands of vultures. I have disturbed 

 many of the vast flocks of these birds, and yet, even now, I can not see 

 one individual passing through the air without following him with 

 my eyes until he disa]>pears in the distant horizon. 



Fruitful observation requires that the model be well chosen. Ordinary 

 observers are C(mtined to the bad examples which are found in their 

 locality. They can only study the flap]>ing birds — the pigeons, the 

 bats, the little insects even. What good is tp be got from studying a 

 model which can not be imitated on a larger scale? It is impossible to 

 reproduce an insect, a sparrow, even a pigeon, upon proportions which 

 will carry a man. No material will bear the strains of wing beats as 

 energetic as those of the sparrow. Steel itself is too weak in proportion 

 to weight. - - - 



