FLYING AND FLYING-MACHINES. 337 



Motu Animalium, that the opinion so long entertained 

 respecting the impracticability of flight must be re* 

 ferred. He compared the relative dimensions of the 

 breast-muscles of birds with those of the corresponding 

 muscles in man, and thence argued that man's frame 

 is altogether unadapted to the use of wings. He com- 

 pared also the relative muscular energy of birds and 

 men, that is, the power of muscles of equal size in the 

 bird and the man ; and was yet further confirmed in' 

 the opinion that man can never be a flying animal. 



But although the reasoning of Borelli suffices per- 

 fectly well to show that man can never fly by attaching 

 pinions to his arms, and flapping these in imitation 

 (however close) of a bird's action in flying, it by no 

 means follows that man must be unable to fly when the 

 most powerful muscles of his body are called into 

 action to move suitably-devised pinions. M. Besnier 

 made a step in this direction (towards the close of the 

 last century) when he employed, in his attempts to fly, 

 those powerful muscles of the arm which are used in 

 supporting a weight over the shoulder (as when a brick- 

 layer carries a hod, or when a countryman carries a 

 load of hay with a pitchfork). But the way in which 

 he employed the muscles of the leg was less satisfactory. 

 In his method, a long rod passed over each shoulder, 

 folding pinions being attached to both ends of each 

 rod. When either end of a rod was drawn down, the 

 descending pinion opened, the ascending pinion at the' 

 other end closing ; and the two rods were worked by 

 alternate downward pulls with the arms and legs. The' 



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