592 RACE AND CIVILIZATION. 



Turning now from words to things, we may perhaps see some ground 

 for further consideration in even one of the best elaborated depart- 

 ments. 



In the much vexed questions of skull measurements, the paucity of 

 clearly defined racial characteristics may make us look more closely as 

 to whether we are working on an analytic or empirical method. In 

 any physical problem the first consideration is the disentangling of 

 variables and isolation of each factor for separate study. In skulls, 

 however, the main measures are the length, which is compounded of a 

 half dozen elements of growth, and the breadth and height, each the 

 resultant of at least three elements. Two skulls may differ altogether 

 in their proportions and forms, and yet yield identical measures in 

 length, breadth, and height. How can any but empirical results be 

 evolved from such a system of measurement alone 1 ? 



A departure from this mechanical method has appeared in Italy last 

 year by Professor Sergi. He proposes to classify skulls by their forms — 

 ellipsoid, pentagonoid, rhomboid, ovoid, etc. This, at least, takes account 

 for the obvious differences which the numerous measurements wholly 

 ignore; and if skulls were crystals, divisible into homogeneous classes, 

 such a system would work, only, like all organic objects, they vary by 

 infinite gradation. 



What, then, lies behind this variety of form? The variety of action 

 in the separate elements of growth. Sergi's ellipsoid type means slight 

 curvatures, with plenty of frontal growth. His pentagonoid means 

 sharper curvatures. His rhomboid means sharp curvatures, with small 

 frontal growth. And so in each class we have not to deal with a geo- 

 metrical figure, but with varying curvatures of the center of each 

 plate of the skull and varying extent of growth from the centers. 



The organic definition of a skull must depend on the statement of 

 the energy and direction of each of the separate elements out of which 

 it is built. The protuberances or eminences are the first point to notice. 

 They record in their curves the size of the head when it attained rigid- 

 ity in the centers of growth. Every person bears the fixed outline of 

 parts of his infant skull. Little, if any, modification is made in the 

 sharpness of the curves between infancy and full growth; perhaps the 

 only change is made in course of the thickening of the skull. Hence, 

 the maximum radius of curvature of each plate of the skull is a most 

 radical measurement, as implying early or late final ossification. In 

 higher races finely rounded skulls with slight curvatures are more often 

 found; and this agrees with the deferred fixation of the skull pointed 

 out by the greater frequency of visible sutures remaining, both effects 

 being probably due to the need of accommodating a more continued 

 growth of the brain. The length of growth of each plate from its cen- 

 ter in different directions regulates the entire form of the skull. The 

 maximum breadth being far back implies that the parietals grow mostly 

 toward the frontal, or vice versa. The top being ridged means that the 



