[cameron] 



THE HUMAN SKULL 



157 



200 mm. was then prepared. This was marked off into twenty equal 

 parts each of course measuring ten millimetres.^ The ordinates for 

 the four cranial outlines weft made proportionate to this standard 

 base line by careful calculation (Fig. 4). On joining the free ends of 

 these ordinates by means of a curved line an approximate outline of 

 the skull resulted. At the frontal and occipital ends extra ordinates 

 had to be inserted, so as to represent more accurately the rapid descent 

 of the curve at these points. The curve for the Java specimen w^as 

 first prepared, and the ordinates afterwards prolonged to the requisite 

 amounts for each of the other three skulls in turn. Thus the glabella- 



C...G- 



Fig. 4. — Is to illustrate the author's "ordinate method" of reconstruction, as used 

 in Figs. 3, 5, and 6. After each cranial tracing was completed the glabella- 

 inion line was drawn and marked off into twenty equal parts. From 

 these points nineteen ordinates were drawn at right angles until they 

 reached the cranial outline. A standard glabella-inion line of 200 m.m. 

 was then prepared and marked off into twenty equal parts. The ordinates 

 for the cranial outlines were made proportionate to this standard base line 

 by careful calculation. On joining the free ends of these ordinates by a 

 curved line the cranial outline resulted. At the frontal and occipital ends 

 extra ordinates had to be inserted of course. The lowest curve was first 

 prepared and the ordinates afterwards prolonged to the requisite amounts 

 for each of the other skulls in turn, as the Fig. shows. 



occipital base line and the twenty-four ordinates for each skull had 

 all to be converted to one standard, an operation which entailed much 

 labour. In fact the various conversions were so numerous that slight 

 errors in the cranial curves have probably crept in. Every reasonable 



^ Figs. 3, 5 and 6 have of course been reduced in the reproduction. 



