238 POPULAR LECTURES AND ADDRESSES. 



directions of rotation of the fly-wheels in the 

 gyrostatic system (Fig. 45) are indicated by 



FIG. 44. 



directional ellipses, which show in perspective 

 the direction of rotation of the fly-wheel of 



are connected one to each of two opposite corners of a four-sided 

 jointed frame, each member of which carries a gyrostat so that the 

 axis of rotation of the fly -wheel is in the axis of the member of 



