SCIENTIFIC FLYING

Gisborne Times, Volume XXXVI, Issue 3430, 6 September 1913, Page 3

SCIENTIFIC FLYING

MANKIND IMITATING BIRDS. ‘‘Now that the era of practical aeroplanes is close upon us, a book such as F. W. Headley’s ‘Flight of Birds’ (Scribner) can command a wide attention,” says the New York “Nation.” “In a volume of some one hundred and fifty pages, Mr Headley has given briefly and clearly the main facts concerning the flight of birds, with interesting side notes on the efforts which mankind is making to imitate them. “The first six chapters deal with the. mode and methouYn flight, Gliding. •Stability, Motive Power, Starting, Stopping, and Alighting. Succeeding chapters discuss the Machinery ■and Rapidity of Flight, Varieties of Wings, and the Relation between Wind and Flight. Although the study of flight involves a thorough knowledge of higher mathematics and physics, the author has kept his treatment of the subject popular.

"From the first it is clear that what man has to think about, the bird does instinctively, and that the only real comparison between the efforts- of birds and men is when the former are sailing or soaring. The comparison of birds of varying size brings forth many points of view, which will be new to most readers. One is that in proportion to his weight the big flyer requires comparatively very small supporting surface. Thus, if a swallow had proportionately a stork’s allowance of wing surface; it would have but two inches in each side, while a gnat would have more than four and a half square yards for a single pound of weight.

"The author discusses the automatic safeguards which birds possess, the frequent cases of body twisting and of steering with feet instead of with the tail, which explain a bird’s •-.ontrol of direction even when the entire tail has accidentally been lost. As regards stability, Mr. Headley states truly that a bird does not maintain a steady, careful equilibrium, but makes a constant readjustment to every gust and vagary of wind. ‘■'The chapter on Pace and Last sums up our knowledge of the rapidity and extent of flight and endurance of birds on migration and at other times. A Fi ench homing pigeon has a record of one hundred and six miles in an hour. The migrants which travel many hundreds of miles oversea without rest undoubtedly subsist upon the fat stored within their own bodies. A bird with a very-., low stroke —say, one hundred and thirty to the minute -•—if on the wing only twelve hours, must contract his flight- muscles more than ninety-three thousand times! From such facts as these one may appreciate the wonderful adjustment of a bird’s heart, wings, and senses.”