Pepper.] 3b4 [Deez2, 
1. It is especially in regard to the explanation of the internal osteopo- 
rosis, which constitutes so marked a feature of these specimens, that we 
regret the absence of any careful examination of the bones in their recent 
condition. Jn their present state, it is only possible to describe the de- 
gree to which this rarefaction of the osseous tissue has occurred, but it is 
evident that such changes might be produced by very varied alterations 
of the medulla and bone corpuscles. Thus, among the recognized causes 
of osteoporosis, may be mentioned syphilis, scrofula, rheumatism ; qnd, 
in addition, we must add that both osteomalacia and simple ostitis pro- 
duce changes in the bones which, after the specimen has been boiled, and 
the organic matter entirely removed, are not to be distingushed from the 
effects of the first mentioned diseases. In each case, under the action of 
the morbid irritant, whether purely external and local, or internal and con- 
stitutional, there is more or less rapid proliferation of the essential vital 
elements of the osseous tissue, called bone corpuscles or cells. At the same 
time, the bony lamin surrounding the Haversian canals, and the walls 
ef the lacunse, are progressively deprived of their calcareous salts and 
removed, while the enlarged spaces thus produced are filled by the con- 
stantly growing cellular elements. The manner in which this removal of 
the caleareous salts is effected has been, and indeed remains, a subject of 
much discussion. The first idea which seems to have been entertained may 
be inferred from the name, eccentric atrophy, which was given to many 
specimens of osteoporosis, under the belief that the bony lamelle were 
thinned and pushed asunder by the centrifugal pressure of the growing 
medulla. There is, however, no evidence whatever in favor of such a 
mechanical explanation, and this hypothesis has justly been almost uni- 
yersally abandoned. 
By far the most plausible explanation which has been advanced appears 
to be that the removal of the calcareous salts, the first essential step in 
the destruction of the bony lamelle, is due to the solvent action of some 
acid elaborated by the bone cells during the inflammatory process. Ac- 
cording to Weber, their removal is not due to the direct action of any 
acid, but is owing to a gradual conversion of the insoluble trt-basie phos- 
phate of lime into the more soluble b2-basie salt. 
As this feature of rarefaction is, however, common to so many diseases 
of the bones, it is evident that the most characteristic results of such dis- 
eases are to be rather found in the condition of the bone cells, and in the 
characters of the morbid product which has resulted from their multipli- 
cation. And it is to be trusted, that by careful chemical and microscopi- 
cal study of these, such peculiarities will be discovered as will enable us 
to distinguish with certainty in recent bones the various morbid changes. 
Heretofore the majority of observers have limited themselves either to 
a description of the dried bone, after maceration or boiling, or at most, 
of the general characters of the medulla with which its cancelli are filled. 
And it results from this swperficial mode of study, that there is as yet but 
om geninn 
cm, aise 
