390 THE ANTIQUITY OF MAN 
which commences on the angular process of the frontal 
bone (fig. 138), ascends vertically for some distance on 
the side of the Piltdown skull before turning backwards. 
In all other kinds of human skulls this line bends back- 
wards almost as soon as it begins to ascend. This 
peculiar feature may be due to a vertical character of the 
forehead, or to a peculiarity in the form- and manner of 
action of the temporal muscle. The other strange feature 
of the Piltdown skull, as seen in profile, is the vertical 
disposition of the suture between the occipital and 
parietal bones (fig. 143).^ 
We have now reached one of the points towards which 
we have been working. We have examined and verified 
the contours and measurements of the Piltdown skull 
from behind, above, and now from the side, with the view 
of obtaining those measurements which give us a clue to 
the brain capacity. We have seen that the width of the 
skull is 150 mm., its length, 194 mm., its auricular height, 
117 mm. Before we can apply to these measurements 
the formulae which are used for estimating the brain 
capacity of the modern skull we must make a reduction 
on account of the thickness of the bones — reducino^ the 
length to 190 mm., the width to 140 mm., the auricular 
height to 112 mm. The formula^ I am to employ to 
obtain the brain capacity is that worked out by Dr Alice 
Lee and Professor Karl Pearson. When that formula is 
applied the result is 190 x 140 x 1 12 x -4 + 206 = 1397 c.c. 
— a brain capacity which is almost the same as that of the 
Egyptian woman's skull which formed the subject of our 
experimental reconstruction. The female skulls found 
in the plague pits of Whitechapel, in the east of London, 
had, on an average, a brain capacity of 1300 c.c. ; the male, 
1477 c.c.^ The brain capacity of the Piltdown skull is 
thus above that of the average modern Englishwoman, 
and below that of the modern Englishman. The actual 
^ See also p. 495. 
- FAt'L Trans., 1899, vol. 196A, pp. 225-264. 
3 See Dr W. R. Macdonell's researches, Bio7nctrika, 1904, vol. iii. 
p. 191. 
