.92 



Mr. C. Chree on Rotating Elastic 



finite values of b/a. The curve crosses the rim at but a small 

 distance from the end of the major axis, and recrosses it at a 

 point whose angular distance from the end of the minor axis 

 is not very small. The curve passes through the centre 

 cutting the minor axis at a finite angle. Thus, at finite 

 distances from the centre, there is radial compression every- 

 where in the neighbourhood of the minor axis. This second 

 area of radial compression is much more considerable than 

 that at the end of the major axis ; but the two areas together 

 are a good deal smaller than the area throughout which the 

 radial strain is an extension. This type of curve is illustrated 

 by fig. 1, which answers to b/a='&, tj = '25. 



Fig. 1.— b/a = -4. 



As b/a increases the area of radial compression at the end 

 of the major axis expands both in length and thickness. The 

 angular distance from the minor axis where the curve re- 

 crosses the rim also increases, but the angle at which the 

 curve cuts the minor axis at the centre diminishes. This 

 latter angle eventually vanishes when b/a reaches the value 

 b 2 /a of Table VI., and we get the type shown in fig. 2, which 

 answers to b/a = '5, rj = '2b. 



Fig. 2.—b/a='5. 



As b/a further increases the points in which the curve cuts 

 the rim continually approach one another, and the point in 

 which it cuts the minor axis recedes from the centre. In this 

 stage we have the constricted type shown in fig. 3, which 

 answers to b/a = '6, 77 = *25. 



