CHAPTER III. — SPECIAL PHYSIOLOGY OF MOVEMENT. 



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the plant is very slow, so that no centrifugal force is set up. The principle of 

 it is that, by slowly rotating a plant by means of a vertical wheel either (as in 

 Fig. 483 B) with the long axis of the plant in the plane of the wheel, or with the 



Fio. 483 (after Knight).— Diagrama illostrating experiments with Knight's machine. A 

 Wheel rotating horizontally on a vertical axis; B, wheel rotating vertically on a horizontal 

 axis. 



