BONE, NON-DECALCIFIED. 421 



may be left to dry. When dry, they should be of an ivory 

 whiteness, and their surfaces exposed by cutting of a uniform 

 dulness. 



Thin sections may then be cut with a saw and prepared by 

 rubbing down with pumice-stone. Compact pumice-stone 

 should be taken and cut in the direction of its fibres. The 

 surface should be moistened with water and the section of 

 bone rubbed down on it with the fingers. When both sides 

 of the sections have been rubbed smooth in this way, another 

 pumice-stone may be taken, the section placed between the 

 two, and the rubbing continued. As soon as the section is 

 thin enough to be almost transparent it is polished by rubbing 

 with water (with the fingers) on a Turkey hone or lithographic 

 stone. Spongy bone should be soaked in gum and dried 

 before rubbing down (but see VON KOCH'S copal process, ante, 

 311, and EHRENBAUM'S colophonium process, 312). 



WEIL (Zeit. f. wiss. Mik., v. 2, 1888, p. 200) gives a process 

 similar to the foregoing, rough sections or portions of bone 

 and teeth being penetrated with chloroform balsam, which 

 is hardened in an oven, or over a water-bath, and then 

 ground. 



ROSE (Anat. Anz., vii, 1892, pp. 512 519 ; Zeit.f. wiss. Mik., 

 ix, 4, 1893, p. 506) points out some precautions that it is 

 well to take. He penetrates first with a mixture of cedar oil 

 and xylol, then with pure xylol, and imbeds in solution of 

 dammar in chloroform or xylol. The method can be combined 

 with Golgi's impregnation. 



NEALEY (Amer. Hon. Mic. Joum., 1884, p. 142; Journ. Roy. 

 Mic. Soc., 1885, p. 348) says that perfectly fresh portions of 

 bone or teeth may be ground with emery on a dentist's lathe, 

 and good sections, with the soft parts in situ, obtained in half 

 an hour. 



WHITE (Journ. Roy. Mic. Soc., 1891, p. 307) recommends 

 the following : Sections of osseous or dental tissue should 

 be cut or ground down moderately thin, and soaked in ether 

 for twenty-four hours or more. They should then be put for 

 two or three days into a thin solution of collodion stained 

 with fuchsin (made by dissolving the dye in methylated spirit, 

 adding the requisite quantity of ether, then the pyroxylin) . 

 The sections are then put into spirit to harden the collodion. 

 After this they are ground down to the requisite thinness 



