402 ORIGINAL AKTICLES. 



applied pressure, this uniformly oblique direction, producing under 

 the most diverse circumstances the same regular irregularity ? 



The first question need not detain us long. It is well known 

 that thin bones when long macerated become quite soft, and can of 

 course be bent. Still, as the posthumous distortion of bones is im- 

 doubtedly an exceptional process, it may be well to glance at the 

 physical and chemical circumstances which seem favourable to its 

 occurrence. To give a distorted skull, the bones must clearly be 

 reduced to a certain condition of plasticity, and yet they must retain 

 enough of their original character to harden and set when dried. 

 To produce this result a certain amount of the organic matter must 

 still remain in the bone, and the bone may be altered in one or in 

 both of two ways ; either the whole bone may be partially decomposed, 

 a part of the mineral and a part of the animal matter being replaced 

 by water, and the bone thus softened, a process which will render 

 the b6ne more and more friable until it is thoroughly disintegrated, 

 or, imder exceptional circumstances, a large part, or the whole, of 

 the mineral matter may be dissolved out, and the animal matter at 

 the same time preserved, the bones thus become light and flexible 

 and yet they retain their integrity. The first of these is the ordinary 

 case of the rotting of bones in a damp churchyard. I shall give one 

 extreme case of the second, to show, not only that the process occurs, 

 but that it may be carried to an almost indefinite extent. The late 

 liev. Prof. Fleming of Edinburgh had in his possession a head of 

 Bos longifrons (Owen) taken from a bog in the south of Scotland, 

 only weighing a few oimces, and, when damped, as flexible as a piece 

 of leather. In this case the mineral matter had been almost entirely 

 removed by some acid produced probably by the fermentation and heat- 

 ing of a portion of the moss, while the animal matter remained tanned 

 and preserved by the antiseptic principles in solution in the bog water. 

 The condition of the distorted skulls may probably be frequently 

 produced by a compromise between these two processes. The bones 

 are imbedded in mould, frequently peat or virgin soil, containing a 

 large proportion of vegetable matter, and probably enough of tannin 

 to retard the decomposition of the chondrine — while the fluids perco- 

 lating through the soil, highly charged with carbonic acid, the product 

 of the decomposition of the vegetable matter, and containing various 

 salts in solution, must gradually decompose and remove the inorganic 

 constituents, thus increasing the flexibility of the bone. My friend 

 Dr. Henry Johnson of Shrewsbury, who has carefully analysed the 

 bone of the Orchard skulls, puts gi'eat faith in the peculiar properties 

 of humic acid.* I find the information on this point somewhat ob- 

 scure. It may be sufilcient at present to indicate the general results, 

 without attempting to trace the actions of the several re-agents. 



Notwithstanding theii- undoubtedly great age, the Orchard skulls 



• Dr. Johnson, in a paper lately read before the Royal Society, and of which a 

 notice will be found in the Royal Society Proceedings, for 1862, states that he be- 

 lieves that free iiitric acid also exists in the soil of the Wroxeter cemetery. 



