44 OSSEOUS CORPUSCLES. 



administering or suspending the madder.* At the same time, 

 that there is this increase of matter on the surface, there is a 

 corresponding enlargement in the central or medullary cavity, 

 which is said to be effected by the action of the absorbents. 

 It appears to me, however, to be far more likely due to an 

 interstitial growth, by which the walls of the cavity are in- 

 creased in dimensions and the cavity itself necessarily enlarged. 

 Corpuscles. Purkinje has -recently Fig. 7.f 



discovered in cartilage generally, and 

 especially in the cartilage of bone, round- 

 ed corpuscles, which are much larger 

 in diameter than the transverse sections 

 of the canals described in p. 30. The 

 existence of these corpuscles, has also 

 been confirmed by the microscopical re- 

 searches of Deutsch, Miescher, Sharpey 

 and others ; according to Miescher they 

 correspond with the brown spots described 

 by Lewenhoeck as his second order of foramina. In bone de- 

 prived of its earthy parts by maceration in acid, their appear- 

 ance is that of small brown spots,{ pellucid in the centre, and 

 surrounded with a distinct opaque line, which by a high magni- 

 fying power, appeared to Miescher to be denticulated. They 

 are situated between their lamellae, the long diameter being ob- 



* Rutherford, of Edinburgh, first explained this coloring of the bone, without 

 that of the other tissues, by the affinity of the madder for the phosphate of litne, 

 upon which it acted as a mordant. p. 



f Fig. 7, is a representation from Miescher of the progress of ossification, 

 caused by inflammation in an adult bone, which takes place nearly in the same 

 manner that new bone is formed ; a a, the cartilage, the first stage in the forma- 

 tion of bone, and the small bodies thickly interspersed through it are the carti- 

 lage corpuscles of Purkinje j b b, the first or primary stage of the bony structure, 

 in which the osseous corpuscles arrange themselves somewhat into lines, and 

 the bony fibres shoot in between them, and in the thickness of the corpuscles 

 themselves saline particles are deposited, which renders them opaque ; c c, the 

 new structure completely ossified. 



$ These as shown p. 46, are now believed to be new bodies, bony corpuscles, 

 which supplant the cartilaginous corpuscles of Purkinje. The above account 

 is retained in order to show progressively the history of the discovery. 



