ITS COMPOSITION IN DISEASES. 23 



C. Schmidt,* and C. O. Weber,f we find very few chemical 

 investigations accompanied with a history of the disease under 

 which the patient laboured. In the absence, therefore, of an 

 accurate history of the case, we can ascertain very little from our 

 numerous analyses of morbid bones, seeing that in the great 

 majority of cases only very unimportant differences are apparent 

 in the composition of very differently named morbid bones. More- 

 over, such different methods have been employed in preparing the 

 bones for analysis, and in conducting the examination, that the 

 results that are obtained do not admit of comparison. 



On entering upon the special examination of the results of 

 these numerous investigations, we have, first of all, to notice the 

 general proposition enunciated by von Bibra, that in almost all 

 morbid processes implicating the bones the mineral substances are 

 abstracted from the tissue earlier and in larger quantity than the 

 organic matter ; and that in almost all diseased bones a relative 

 increase of the cartilage is observed. The bone-earth is not only 

 earliest separated from already formed bones during morbid con- 

 ditions, but it is also last deposited in the bones after the cessation 

 of disease, as, for instance, is seen in the composition of the scle- 

 roses ; for a bone, or a part of a bone, often exhibits the most 

 decided physical characters of sclerosis when the earthy consti- 

 tuents are far below the normal average. It is an error to suppose 

 that in sclerotic bones there is more earthy matter and less 

 cartilage than in normal bones. This much only is true, that in 

 consecutive sclerosis, that is to say, after osteoporosis or osteo- 

 malacia the bone gradually recovers its earthy constituents, although 

 not always to such a degree as to reach the normal proportion 

 between the inorganic and organic matters. At all events, the 

 analyses of Ragsky and Baumert do not prove more than this. 



The cartilage is very rarely affected in morbid bones. Most 

 observers have obtained the ordinary glutin from the cartilage of 

 diseased bones. (In some cases of very decided rachitic bones 

 both Marchand and I have failed to obtain any true glutin.) 



The amount oifat in the bones has only been accurately deter- 

 mined in a few cases ; but von Bibra's analyses lead to the infer- 

 ence, that generally when, in consequence of disease, a bone has 

 suffered a loss of earthy matter, and still more of its cartilage, the 

 quantity of its fat is increased. 



* Ann. d. Ch. u. Pharm. Bd. 61, S. 329. 



t Commentatio praemio ornata. Bourne, 1851. i 



