VII.] 



DISCUSSION OF THE DATA OF STATURE. 



101 



tical one, the sum of the entries in the four adjacent 

 squares. I then noticed (see Fig. 11) that lines drawn 

 through entries of the same value formed a series of 

 concentric and similar ellipses. Their common centre 

 lay at the intersection of those vertical and horizontal 

 lines which correspond to the value of 68^- inches, as 

 read on both the top and on the side scales. Their 

 axes were similarly inclined. The points where each 

 successive ellipse was touched by a horizontal tangent, 

 lay in a straight line that was inclined to the vertical in 



the ratio of -§-, and those where the ellipses were touched 

 by a vertical tangent, lay in a straight line inclined to 

 the horizontal in the ratio of ^. It will be obvious 

 on studying Fig. 11 that the point where each suc- 

 cessive horizontal line touches an ellipse is the point 

 at which the greatest value in the line will be found. 

 The same is true in respect to the successive vertical lines. 

 Therefore these ratios confirm the values of the Ratios 

 of Regression, already obtained by a different method, 

 namely those of § from Mid-Parent to Son, and of 



