22 OSSEOUS TISSUE. 



mammals or birds. According to Stark, the bones of fishes con- 

 tain more water than those of any other animals. 



Notwithstanding the enormous number of analyses of morbid 

 bones which have been made by different chemists, very few results 

 with any claim to certainty have been obtained regarding the com- 

 position of the bones in definite diseases. To this unfortunate 

 circumstance we must in a great measure ascribe the difficulties 

 which present themselves in diagnosing diseases of the bones 

 during life, and often even after death, if we regard the diseased 

 bone merely as an isolated pathologico-anatomical specimen. We 

 need only refer to the osteomalacia of children (rachitis) and of adults, 

 to the different kinds of osteoporosis, to primitive and consecutive 

 scleroses, to the various osteophytes and ivory-like exostoses, 

 &c. It appears to be often difficult, without a previous knowledge 

 of the mode in which the bone-disease was developed, to give a 

 decided opinion on its nature, even when it is brought before us as 

 a piece of morbid anatomy. We are, moreover, inclined to believe, 

 without in any way criticising the anatomical observations hitherto 

 made in connection with diseases of the bones, that the whole 

 subject requires further development in a pathologico-anatomical 

 point of view. The chemist must therefore be pardoned if (as has 

 more than once happened) he should mistake osteoporosis for 

 osteomalacia, if he should regard an osteopsathyrosis as softening of 

 the bones, and not as a subdivision of osteoporosis ; in short, if in 

 many cases he should confound osteoporosis with osteomalacia, and 

 rachitis with caries. It is no wonder, then, if in the analysis of 

 osteoporotic bones we rarely or never ascertain whether the rare- 

 faction of the osseous tissue depends upon a simple syphilitic, 

 arthritic, or tuberculous ostitis, or on an excessive growth of 

 medulla, or on simple atrophy of the bony tissue ; that is to say, 

 upon the disappearance of the above-mentioned concentric osseous 

 lamellae from the Haversian canals. Nor need we wonder that we 

 are yet so comparatively ignorant regarding the chemical consti- 

 tution of the osteoscleroses ; for excepting the analyses of Ragsky,* 

 von Bibra,f SchlossbergerJ Gerster, Gruber and Baumert,|| 



* Rokitansky's Handb. d. pathol. Anat. Bd. 2, S. 201-205 [or English 

 translation, Vol. 3, pp. 180-182.] 



f Arch. f. phys. Heilk. Bd. 6, S. 287-299. 



t Ibid. Vol. 8, pp. 69-87. 



Ibid. Vol. 6, pp. 142-14G. 



H Beitriige z. Anat. Physiol. u. s. w. 2 Abth. Prag. 1847. 



