BONE, DECALCIFIED. 423 



a superior preservation of the structures. Sections of fresh 

 teeth, not thicker than 0*75 mm., are made with a saw, and 

 put into a mixture of six parts 1 per cent, gold chloride and 

 three parts pure formic acid, for twenty-four hours. Wash 

 with distilled water, and reduce for twenty-four hours in gly- 

 cerin gum solution. Pass through water and alcohol and 

 imbed in celloidiu or paraffin, and cut. The dentinal canaliculi 

 are shown stained. 



Bone can be treated in the same way. 



For UNDEKWOOD'S gold process for teeth see 228. 



799. VIVANTE (Intern. Monatssch. f. Anat. u. Phys., ix, 1892, 

 p. 394 ; Zeit. f. wiss. Mik., ix, 3, 1893, p. 351) has made out that 

 thin specimens of bone can be successfully treated by Golgi's 

 bichromate of silver process. He places portions of frontal bone 

 of four to six months calves, which are not more than 3 to 

 4 mm. thick, for eight days in solution of Miiller, then in the 

 osmium bichromate mixture, and then in the silver solution. 

 After impregnation the specimens should be decalcified, which 

 may be done by putting them for twenty days into von 

 Ebner's mixture ( 563), after which they should be well 

 washed with water and brought into solution of carbonate of 

 soda, and finally imbedded in paraffin. 



Another method recommended by Vivante is as follows : Fix for five or 

 six days in solution of Flemming, wash and decalcify with von Ebner's 

 mixture, wash, treat with carbonate of soda, imbed in paraffin, cut, and stain 

 the sections for an hour in 0'2 per cent, solution of quinolei'n blue ( 126). 

 Wash out in equal parts of alcohol and water followed by pure water, dry 

 the sections in a stove at 40 C. (both alcohol and glycerin must be avoided), 

 clear with bergamot oil, and mount in damar. Nuclei violet, protoplasm and 

 ground substance different shades of blue. 



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

 p. 47). Sections of delcacified 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 



