126 
Cranial Type- Contours 
We now took the horizontal line through the nasion, i.e. the line linking t.he 
nasion to the gamma as our " horizontal axis " and divided it into ten equal pieces 
by aid of the proportional compasses. The nasion counting as 0, and the other s 
from nasion to gamma as 1, 2, 3, 4... 9, lines are drawn through these ten. 
points perpendicular to the horizontal axis ; a further upright is taken near the 
gamma at one quarter the distance from gamma to 9 ; this for brevity is termed 
the 7^ line. At 0, i.e. vertically through the nasion, there will, in most male 
skulls, be a sensible ordinate, roughly of about 2 cm. In order to get the curvature 
in the neighbourhood of the glabella a vertical tangent was drawn by aid of the 
set-square to the most projecting part of the glabella; the point in which this 
tangent meets the prolonged gamma-nasion line being T and the point of contact 
of the tangent being G, GT and TN represented by the letters y and x respectively 
were measured, they are practically the coordinates of the glabella, and average 
roundly about 10 mm. and 3 mm. respectively for male skulls. Occasionally, but 
rarely, the glabella tangent cuts the horizontal axis between the nasion and 
gamma ; in such cases x is to be reckoned as negative. Lastly, to complete the 
drawing of the frontal part of the sagittal contour, an extra ordinate was measured 
at \ the distance from 0 to 1 ; this line is spoken of as the N\ line. We have 
thus three points, the tangent at one of them and the nasion defining the nature 
of the contour in the glabellar part of the skull, and these were found amply 
sufficient to reproduce the individual contour as closely as it could be redrawn by 
the Klaatsch. A knowledge of Ny and of the coordinates of the thirteen points 
sufficed to reproduce the whole contour by aid of a spline. Our record book had 
therefore the following entries : 
Ny 
X 
y 
0 
i 
2 
3 
4 
5 
6 
7 j 8 
9 
yi 
Of course in addition to these we had all the tjqrical points of the sagittal 
section, and the measurements, lengths and angles advocated by Schwalbe (see 
Zeitschrift fur Morphologie, Bd. I. S. 38). It should be at once noted that 
nasion to gamma is not any recognised length on the head or the skull ; it is not 
the maximum length, nor the length from lambda to nasion, nor the horizontal 
length (see Biometrika, Vol. I. p. 414). It is chosen simply as a convenient 
horizontal base line by which to fix our system of axes, and measure our ordinat.es. 
If in taking the height of a man, the level of his eyes be marked off, and he be 
asked to look at this mark from several yards' distance, the head will be very nearly 
in a horizontal position (e.g. the horizontal position of Broca). A horizontal plane 
through the nasion will now very closely determine the gamma on the sagittal 
section, and this can be marked off on the flexible lead strip* which at the 
suggestion of Dr Charles Goring was used to give the sagittal section of the living 
head. The calliper measure of Ny suffices to test the accuracy with which the 
* 1 cm. deep by 1 mm. thick. 
