10 PKEHISTOEIG TEEPPIINING. 



occasionally cut off a slice of the cranium, but it certainl}- could not cut 

 out rondelles from the parietal bones. (See Plate IV.) 



Contused wounds, such as would be produced by rude weapons, pro- 

 duce necrosis or death of the bone, an(f where healing- takes place irregular 

 apertures remain, entirely unlike the result of a surgical operation. 



The reparative process in wounds of the cranium in the adult is one 

 of extreme slowness. An osteitis, or inflammation of the bone, is set up, 

 which extends to some distance from the edges of the wound. The vascular 

 canaliculi of the two tables beconie dilated, and it is often yeai-s before 

 they recover their normal caliber. But in the skulls under discussion, in 

 all instances, the edges of the aperture made by surgical trephining exhibit 

 the most perfect readjustment of the parts. This is the case in young as 

 well as in old crania; in one in.stance particular!}-, that of a woman of less 

 than twenty-five years of age, the wisdom teeth being still in process of 

 development, the traces of the traumatic inflanuuation have as completely 

 disappeared as in the skulls of very old persons. This led Broca to believe 

 that the operation must have been performed at a very early age, and other 

 observations tend to confirm that theory. Although the operation of tre- 

 phining, as before stated, is not a very dangei'ous one when uncomplicated 

 by injury to the brain, yet it would be unreasonable to suppose that it was 

 never fatal. If sometimes fatal, we should exj)ect to find skulls exhibiting 

 the evidence of partial recuperative process. But, with one exception, no 

 such relics have been discovered; the edges of the openings are either 

 absolutely fresh, indicating post-mortem work, or absolutely cicatrized, 

 indicating that the operation had been performed many years before the 

 death of the subject. What then became of the failures"? 



If the operation was performed only on young children, then the rapid 

 decay of their tender bones would answer the question. In dolmens con- 

 taining a large number of adult crania, it is usual to find nothing but mere 

 debris of the bones of children, and in the case of trephined .skulls, the thin 

 edges of the apertures would ofter favoi-able points for the chemical and 

 physical agency of ei'orion. 



It is unnecessary to relate all the observations and arguments which led 

 Broca to the conclusion that prehistoric trephining was perfoi-med mainly, 



