PEOFESSOE THOMSON ON DISTORTED HUMAN SKULLS. 401 



of a skull from a cist in Orkney. The distortion is not so strongly 

 marked in this as in the two former cases, and the character of the 

 distortion is slightly different. In most cases of skull twisting the 

 bones of the face have escaped distortion, by separating from the 

 bones of the head — in this they have remained attached and have 

 become involved in the change of form. In the two former cases, the 

 crania posterior to the coronal sutures remained nearly normal, in 

 this case the whole of one side of the skuU has been forced sUghtly 

 inwards, forcing out and bulging the opposite side to a corresponding 

 degree. Erom the difference in position, the twist in the frontal 

 bone is not so evident, but the axis of distortion of that bone, when 

 projected, follows almost exactly the same course as in the two 

 former occasions. 



From these three, and from many other examples of skuUs, whose 

 distortions present essentially and closely the same features, out- 

 numbering by ten to one the cases in which there is the slightest 

 difficulty in referring the distortion to this common type, I conclude 

 that a peculiar and definite form of distortion of the human skull, 

 varying in degree, but constant in essential characters and physiogno- 

 mic effect, is extremely common in connection with ancient burial, 

 and that it is totally independent of period, and of race, and nearly 

 so of the original form of the head. The first question which sug- 

 gests itself is whether this distortion was caused by a system of 

 artificial pressure and bandaging during life, or by posthumous 

 changes. That the distortion was posthumous I believe we have 

 ample proof In the three cases described the change is com- 

 paratively slight. The distortion is frequently carried further, though 

 still in the same direction, till the deformity produced is evidently 

 inconsistent with life ; before this occurs, however, the sutures most 

 usually give way, and the skuU fttlls to pieces. When this has been 

 the case, it has often been found that still fm-ther changes have taken 

 place in the form of the individual bones, and that they will not fit 

 at the sutures, when put in position. This circmnstance has already 

 been adduced by Mr. Davis as an argument in favour of posthu- 

 mous changes in the form of bones. To my mind, however, we have 

 the most absolute proof in the systems of cracks traversing the bends. 

 These cracks have perfectly sharp edges, so that they could not pos- 

 sibly have been produced by slow pressure during life. They are 

 almost microscopic where the curve is slight, increasing in width and 

 depth with the abruptness of the bend, and in some cases the bone 

 has given way along their course, breaking short off". They are evi- 

 dently the result of unequally supported pressure, on dead bone, 

 reduced to an imperfectly plastic condition. The change in form was 

 then posthumous, due to tomb-pressure, and the range of inquiry is 

 narrowed to the two questions : What circixmstances reduce the thin, 

 bones of the skull to that peculiar plastic condition in which they 

 are softened without being disintegrated, and bent without giving, 

 way at the sutures ? And wliat cause has given the subsequently 



