282 CHAPTER XXIV. 



559. Nitric Acid and Formol. SCIIRIDDE (Hfematol. Techn., 

 Jena, 1910, p. 21) decalcifies material fixed in formol or 

 formol-Miiller in a mixture of 1 part of formol, 1 of nitric 

 acid, and 9 of water. 



560. Nitric Acid and Alum (GAGE, quoted from FISH, 558). 

 A saturated aqueous solution of alum is diluted with an 

 equal volume of water, and to each 100 c.c. of the dilute 

 solution is added 5 c.c. of strong nitric acid. Change every 

 two or three days, until the decalcification is complete. For 

 teeth this is said to be, perhaps, a better decalcifier than the 

 alcohol mixture. 



561. Sulphurous Acid (ZTEGLEI?, Festsclir. /. Nupffcr, 1899, 

 p. 51). A saturated solution in water. Wash out for 24 

 hours. Acts rapidly and preserves well. Best used after 

 fixation with formol. 



562. Hydrochloric Acid (see 555). RANVIER says that it may be 

 taken of 50 per cent, strength, and then has a very rapid action. To 

 counteract the swelling action of the acid, sodium chloride may be added 

 (VON EBNER), see HAUG'S paper quoted 555. He takes either 100 c.c. 

 cold saturated solution of sodium chloride in water, 100 c.c. water, and 

 4 c.c. hydrochloric acid. Preparations to he placed in this, and 1 to 2 c.c. 

 hydrochloric acid added daily until they are soft. Or, 2'5 parts of 

 hydrochloric acid, 500 of alcohol, 100 of water, and 2'5 of sodium chloride. 

 HAUG prefers the proportions of TO to 5'0 of acid, 70 of alcohol, 30 of 

 water, and 0'5 of salt. 



563. Hydrochloric Acid and Chromic Acid (BAYERL, Arcli. mil:. 

 Anat., 1885, p. 35). Equal parts of 3 per cent, chromic acid and 1 per 

 cent, hydrochloric acid. For ossifying cartilage. HAUG recommends 

 equal parts of 1 per cent, hydrochloric acid and 1 per cent, chromic acid 

 (loc. cit.). 



564. Hydrochloric Acid and Glycerin. Glycerin, 95 ; hydrochloric 

 acid, 5 (SQUIRE'S Methods and Formula, p. 12). 



565. Trichloracetic Acid. PARTSCH (Verl. 6V*. D. Naturf. 

 Aoize, 1895, 2 Tlic.il, 2 Halfte, p. 26) uses a 5 per cent, 

 aqueous solution, and NETJBERGER (Ccnfmlh. Pliys., xi, 1897, 

 p. 494) a 4 per cent. one. Action energetic, preservation 

 said to be excellent. 



