CARTILAGE (AND DECALCIFIED BONE). 347 



690. Bone, Decalcified (FLEMMING, Zeit. f. wiss. Mik., 1886, 

 p. 47). Sections of decalcified bone are made with the free 

 hand. They are soaked in water, and brought in a drop of 

 water on to a glass plate where they are spread out flat. The 

 excess of water is removed with blotting-paper, and the 

 sections are covered with another glass plate, to prevent them 

 from rolling. The whole is brought into a plate and covered 

 with alcohol. After the lapse of half an hour, the sections 

 have become fixed in the flat position, and may be brought 

 into absolute alcohol without risk of their rolling. To mount 

 them, wash them with fresh alcohol (which may be followed 

 by ether) ; lay them again flat on glass, and cover them with 

 a double layer of blotting-paper and a somewhat heavy glass 

 plate, and let them dry for a day in the air or in a stove. 

 When they are dry, put a drop of melted balsam on a slide, 

 and let it spread out flat and cool. Prepare a thin glass 

 cover in the same way, put the section on the prepared slide, 

 cover it with the prepared cover, put on a clip, and warm. 



By this process, sections can be very expeditiously pre- 

 pared, which show the lacunar system injected with air in 

 quite as instructive a manner as non-decalcified sections. 



KOLLIKER (Zeit. f. wiss. ZooL, xliv, 1886, p. 662) recom- 

 mends the following process for the demonstration of the 

 " fibres of Sharpey " in decalcified bone. Sections are treated 

 with concentrated acetic acid until they become transparent, 

 and are then put for one quarter to one minute into a con- 

 centrated solution of indigo-carmine, then washed in water 

 and mounted in glycerin or balsam. In successful prepara- 

 tions the " fibres of Sharpey " appear stained of a pale or 

 dark red, the remaining bone- substance blue. 



691. Cartilage (and Decalcified Bone), For an excellent 

 discussion (especially as regards staining) of the methods 

 that have been recently recommended for these objects, see 

 the exhaustive paper of SCHAFFER in Zeit. f. wiss. Mik., v, 1, 

 1888, which gives in sufficient detail all the methods in ques- 

 tion. The following appear to be the best : 



RANVIER'S purpurin method. This has been given in detail 

 in 189. 



SCHAFFER'S safranm method. This methou : s due in its 

 principle to BOUMA (Centralb. f. d. med. Wiss., 1883, p. 866). 



