 | Philip Henry Gosse - 1849 - Страниц: 344
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in that fluid (in which there is so little friction) cannot be great; and this force is all that is wanted.... | |
 | William Dowling - 1849 - Страниц: 356
...if the extended wings formed the fulcrum on which the movements of the neck, body, and tail acted. It is truly wonderful and beautiful to see so great a bird, hour after hour, without any apparent exertion, wheeling and gliding over mountain and river." It is only... | |
 | John George Wood - 1862 - Страниц: 804
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in that fluid (in which there is so little friction) cannot be great, and this force is all that is wanted.... | |
 | John George Wood - 1862 - Страниц: 804
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in that fluid (in which there is so little friction) cannot be great, and this force is all that is wanted.... | |
 | John George Wood - 1862 - Страниц: 804
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in that fluid (in which there is so little friction) cannot be great, and this force is all that is wanted.... | |
 | John George Wood - 1831 - Страниц: 802
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in that fluid (in which there is so little friction) cannot be great, and this force is all that is wanted.... | |
 | Aeronautical Society of Great Britain - 1883 - Страниц: 488
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal...wonderful and beautiful to see so great a bird hour after hour, without any apparent exertion, wheeling and gliding over mountain and river." So far as... | |
 | Henry Mills Alden, Frederick Lewis Allen, Lee Foster Hartman, Thomas Bucklin Wells - 1871 - Страниц: 980
...action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal...in the air (in which there is so little friction) can not be great, and this force is all that is wanted. The movement of the neck and body of the condor... | |
 | Henry Mills Alden, Frederick Lewis Allen, Lee Foster Hartman, Thomas Bucklin Wells - 1871 - Страниц: 968
...inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep op the momentum of a body moving in a horizontal plane...in the air (in which there is so little friction) can not be great, and this force is nil that is wanted. The movement of the neck and body of the condor... | |
 | Charles Darwin - 1879 - Страниц: 452
...the rapid descent seemed to urge the bird upward with the even and steady movement of a paper kite. It is truly wonderful and beautiful to see so great a bird, hour after hour, without any apparent exertion, wheeling and gliding over mountain and river. THE OSTRICH.... | |
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In the case of any bird soaring, its motion must be sufficiently rapid, so that the action of the inclined surface of its body on the atmosphere may counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in... 
