254 DECALCIFICATION, DESILICIFICATION, ETC. 



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

 4 c.c. hydrochloric acid. Preparations to be placed in this, ajid 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 1-0 to 5-0 of acid, 70 of alcohol, 30 of 

 water, and 0-5 of salt. 



555. Hydrochloric Acid and Chromic Acid (BAYERL, Arch. mik. 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.). 



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

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



557. Trichloracetic Acid. PARTSCH (Verh. Ges. D. Naturf. 

 Aertze, 1895, 2 Theil, 2 Halfte, p. 26) uses a 5 per cent, aqueous 

 solution, and NEUBERGER (Centralb. Phys., xi, 1897, p. 494) a 

 4 per cent. one. Action energetic, preservation said to be excellent. 



558. Picric Acid should be taken saturated arid changed frequently. 

 Its action is weak, but it gives good results with small objects.. 



Picro-nitric or Picro -hydrochloric Acid. Action very rapid. 



559. Phosphoric Acid. 10 to 15 per cent. (HAUG, loc. cit. in 547). 

 Somewhat slow, staining not good. According to SCIIAFFER, 549, it 

 produces swelling. 



560. Lactic Acid. 10 per cent, or more. Fairly rapid, preserves well, 

 and may be recommended (HAUG, loc. cit.). 



561. Chromic Acid is employed in strengths of from 0-1 per cent, to 

 2 per cent, (but see 547), the maceration lasting two or three weeks (in 

 the case of bone). It is better to take the acid weak at first, and increase 

 the strength gradually. Action excessively slow. 



562. Chromic and Nitric Acid. SEILER (FoL, Lehrb., p. 112) takes 

 70 volumes of 1 per cent, chromic acid, 3 of nitric acid, arid 200 of water. 

 The action is still excessively slow, frequently requiring months to be 

 complete. 



563. Chromo-aceto-osmic Acid (VAN VER STRICHT, Arch. Biol., ix, 

 1889, p. 29 ; and SCHAFFER, Zeit. wiss. Mik., x, 1893, p. 179). 

 Objects to be left in it for months, the liquid being changed at first 

 every two days, afterwards less frequently. Structure well pre- 

 served. 



564. Arsenic Acid. 4 per cent, aqueous solution, used at a tempera- 

 ture of 30 to 40 C. (SQUIRE'S Methods and Formula, etc., p. 11). 



565. Phlorogluein with Acids (ANDEER, Centralb. med. Wiss., xii, 

 xxxiii, pp. 193, 579 ; Intern. Monatsschr., i, p. 350 ; HAUG, Zeit. wiss. 



