400 



HARRIS H. WILDER. 



and have nothing to do primarily with the ridges of the pattern 

 itself. 



Turning now to the latter there seems to be one distinct line 

 of modification affecting the center of the Whorl ; the effect of a 

 shoving of the two halves in opposite directions. This action is 

 most readily seen, and its effect comprehended, by drawing out 

 upon a card a series of concentric circles of the same width, 

 cutting the figure in two through the center, and then slipping 

 the two parts on each other to any distance desired. 



Frequently this slipping past of the ridges upon the two sides 

 affects only the central portion of the pattern area, giving a 



FIG. 14 FIG. 15 



FIG. 14. An S-shaped pattern, showing an axis of slipping unlike that of Fig. 13. 



FIG. 15. An S-shaped pattern, showing an axis of slipping 



unlike those shown in Figs. 13 and 14. 



result quite like an ordinary Whorl, with an S in the center (Fig. 

 12). In such cases it remains only to be determined the axis of 

 the slipping, that is, the line along which the diagram of Fig. 10 

 must be cut in order to slip in such a way as to produce the 

 exact pattern we have before us (Figs. 13, 14, and 15). 



In other cases, however, where the extension of the slipping 

 spreads the two half-loops further and further apart, the pattern 

 may become spread out so far that the S-shaped figure covers 

 practically the entire hypothenar area, thus producing an actual 

 double figure, or a figure with two distinct loops, and even a 



