X Preface. 



underlies the classiiication here adopted, is that enunciated 

 by Lister* in 1858, and emphasised afterwards by Cohnheim, 

 Burdon Sanderson, and others, namely, that Inflammation is 

 not so much a disease in itself as a consequence of inter- 

 ference with the vitality of the tissues. Causation of 

 Inflammation has therefore been chosen as the basis of primary 

 subdivision, and the modes of interference with vitality, or 

 causes of Inflammation, are thus the distinguishing features 

 of the larger groups. Although it is difficult to conceive 

 how much we may still have to learn on this subject, the 

 knowledge acquired in recent years seems sufficient to justify 

 the plan adopted, even should it require to be afterwards 

 modified. As it stands, this plan carries with it at least two 

 distinct advantages. Museum specimens are by its means 

 arranged in accordance with present clinical and pathological 

 knowledge. This is obvious, but in addition the confusion 

 which has so frequently arisen from a " cross classification " 

 has been avoided. Such headings as " Necrosis," " Periostitis," 

 and " Syphilis " are commonly used as co-ordinate yet distinct 

 subdivisions of bone disease ; but as the first indicates 

 " result," the second " locality," and the third " causation," the 

 groups are not mutually exclusive, and uncertainty and con- 

 fusion is the necessary consequence. The place for " result " 

 as a basis of subdivision of diseased bones seems to be within 

 each of the larger groups formed upon the basis of " causa- 

 tion," to which it thus becomes of subsidiary importance. 

 In the case of Syphilitic diseases of bone, those of the 



* Philosophical Transactions, 1858. 



