74 Professor D. Wilson’s [llustrations of the Significance 
of the ancient Briton, Roman, Saxon, and Scandinavian, 
apart from any aid derived from the evidence of accom- 
panying works of art. But if it be no longer disputable 
that the human head is liable to modification from external 
causes, so that one skull may have been subjected to lateral 
compression, resulting in the elongation and narrowing of 
its form; while another, under the influence of occipital 
pressure, may exhibit a consequent abbreviation in its length, 
accompanied by parietal expansion; it becomes indispen- 
sable to determine some data whereby to eliminate this 
perturbing element before we can ascertain the actual sig- 
nificance of national skull-forms. If, for example,—as 
appears to be the case,—the crania from British graves of 
Roman times reveal a different form from that of the mo- 
dern Celtic Briton, the cause may be an intermixture of 
races, like that which is clearly traceable among the mingled 
descendants of Celtic and Scandinavian blood in the north 
of Scotland; but it may also be, in part or wholly, the 
mere result of a change of national customs following natu- 
rally on conquest, civilisation, and the abandonment of 
Paganism for Christianity. 
It is in this respect that the artificial causes tending to 
alter the natural conformation of the human head invite 
our special study. They appear at present purely as dis- 
turbing elements in the application of craniological tests 
of classification. It is far from improbable, however, that, 
when fully understood, they may greatly extend our means 
of classification, so that when we have traced to such causes 
certain changes in form, in which modern races are known 
to differ from their ethnical precursors, we shall be able to 
turn the present element of disturbance to account, as an 
additional confirmation of truths established by inductive | 
craniology. Certain it is, however, whatever value may 
attach to the systematising of such artificial forms, that 
they are of frequent occurrence, apart altogether from such 
configuration as is clearly referrible to the application of 
mechanical pressure in infancy with that express object in 
view ; or again, as is no less obviously the result of post- 
lumous compression. But though the deforming processes 
designedly practised among ancient and modern savage 
eee 
