324 Mr. J. H. Vincent on Models and Diagrams to 



The ellipse may be set out from the table given above for 

 the section of ellipsoid of elasticity by the ZOX plane by 

 reducing the figures in the ratio of 3 : 2. 



Fig. 5. 



The foci of the ellipse are indicated by crosses. The curve 

 marked 2 is the section of the outer surface by the plane 

 ?/ = 2. This plane touches the inner sheet on the axis of y and 

 thus (see footnote above) curve 2 goes through the foci of 

 the ellipse. 



