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New Zealand Tablet, Volume IV, Issue 180, 8 September 1876, Page 14

Dr. Edmond Alix has published a work entitled " Essai sur I'A.ppareil Locomoteur des Oiseaux," in which the mode of locomotion has been determined by a careful study of the anatomy of birds. His conclusions on this point are contained in the propositions :—": — " First. The wing in its downward stroke begins by moving forward to attain its basis of support; after which it strikes briskly from above downward, and at the same time from before backward, as a result of which the bird is projected forward. Second. At the moment at which the wing commences to descend, its lower surface looks forward ; but as it descends this surface gradually turns to look directly downward, and ultimately more and more backward. Third. During the ascent of the wing it moves upward and forward, its lower surface at the same time looking forward." This agrees closely with Marey's results obtained by mechanical appliances to birds in flight, but the two investigators differ on the question whether the variation in the inclinations is due to its structure, or merely to the effect of the air upon its flexible posterior margin. Dr. Alix takes the former view.