M. TATIN'S BIRD. 



M. TATIN'S BIRD. 



This apparatus, looked at sideways or from behind, is composed of a 

 light wooden frame, on which are two small supports crossed by an axletree 

 so as to form two cranks. This axle receives a circular movement from an 

 india-rubber spring. The crank on the foremost plane causes the rising and 



Fig. 478. M. Tatin's bird. 



falling of the wings, which move round a common axis, and pass the dead 

 points as the cranks of a locomotive do so the action is maintained. 



But the wing does not only move as a whole ; every part of it, 

 particularly as it rises, shows a tendency to inclination, which is most 



Fig. 478 a. Detail of fig. 478. 



marked towards the extremity ; the part near the body alone preserves 

 an invariable obliquity. M. Tatin was of opinion that it is with the 

 screw that it is necessary to direct the twisting movement; and to obtain 



