442 CHAPTER XXXIII. 



filter is brought back into the capsule, and there boiled with 

 200 c.c. of 94 per cent, alcohol. Allow to cool, filter, make 

 up the filtrate to 200 c.c. with alcohol, and add 4 c.c. of 

 hydrochloric acid. 



Stain sections (of material fixed in any way) for twenty 

 minutes to an hour, wash with alcohol, clear with xylol (not 

 with an essence). Elastic fibres dark blue on a light ground. 

 Nuclei generally unstained ; they may be after-stained with 

 carmine, etc. 



Bone* 



801. Bone, Non-decalcified (RANVIER, Traite, p. 297).- 

 RANVIKR points out certain precautions that it is necessary to 

 take in the preparations of sections of dry bone. In general 

 the bones furnished by " naturalists " or procured in ana- 

 tomical theatres contain spots of fatty substance that prevent 

 good preparations from being made. Such spots are formed 

 when bones are allowed to dry before being put into water 

 for maceration ; when a bone is left to dry the fat of the 

 medullary canals infiltrates its substance as fast as its water 

 evaporates. 



Bones should be plunged into water as soon as the sur- 

 rounding soft parts have been removed, and should be 

 divided into lengths with a saw whilst wet. The medulla 

 should then be driven out from the central canal by means 

 of a jet of water ; spongy bones should be submitted to 

 hyclrotomy as follows : An epiphysis having been removed, 

 together with a small portion of the diaphysis, a piece of 

 caoutchouc tubing is fixed by ligature on to the cut end 

 of the diaphysis, and the free end of the piece of tubing" 

 adapted to a tap through which water flows under pressure. 



As soon as the bones, whether compact or spongy, have 

 been freed from their medullary substance they are put to 

 macerate. The maceration should be continued for several 

 months, the liquid being changed from time to time. As 

 soon as all the soft parts are perfectly destroyed, the bones 



* For a minutely detailed review (40 pages, with references to 80 

 memoirs) of the whole subject of the technique of bone, see the paper of 

 ScHA'fFEE, Die Methodik dcr histologischen Untersuchung des Knochen- 

 yeivebes, in Zeit.f. wiss MiJc., x, 2, 1893, p. 167. 



