BLOOD AND GLANDS 415 



mixture of 1 part formol with 3 parts liquid of Miiller or \ per 

 cent, chromic acid ; Ciechanowski {Anal. Anz., xxi, 1902, 

 p. 426) uses Weigert's myehn stain (1885 method), Eppinger 

 (Ziegl. Beitr., xxxi, 1902, p. 230) hardens five to ten days in 10 per 

 cent, formol, and transfers for ten days to Weigert's ghabeize 

 (§ 1083) at room temperature or for live days at 37° C. One may 

 also mix this with the formol in fixation (11 parts beize to 1 part 

 formol). This is preferable in the case of fresh material. Pieces 

 are then washed in water, hardened in alcohol and imbedded in 

 celloidin. Sections are placed in 1 per cent, haematoxylin (fresh 

 hajmatoxylin twenty-four hours, old solutions fifteen minutes). 

 He then transfers to a concentrated solution of copper-acetate 

 in water for five minutes and to distilled water for an indefinite 

 period (one to two days if desired). The tissue is then differentiated 

 in Weigert's borax ferricyanide solution (diluted 1 in 5 to 1 in 

 9). The undiluted solution is used only with over-stained sections. 

 After well washing he transfers to a concentrated solution of 

 lithium carbonate until the brown staining of the celloidin is lost. 

 Sections are then well washed and mounted. 



Otami (Proc. New York Path. Soc, xxvi, 1926, p. 2) tans 

 paraffin sections of material not fixed in either alcohol or 

 Kaiserling's fluid, for one to two hours in a saturated solution of 

 potassium bichromate at 37° C. Washes five to ten seconds in 

 distilled water and stains five to sixty minutes at 37° C. in 

 Kultschitzky's haematoxylin (§ 1059). This is then differentiated in 

 Weigert's borate solution (§ 1056), passed through alcohol into 

 xylol and mounted in balsam. The bile ducts are blue to brown. 

 Results are variable. 



McIndoo {Arch. Path., vi, 1928, p. 598) uses the following 

 modification of the Rio Hortega silver carbonate stain (Fontana). 

 Small blocks are fixed at least twenty days in 10 per cent, formal- 

 dehyde, and frozen sections cut as thinly as possible. Five or 

 six sections are taken and are heated and cooled for twenty 

 minutes in a silver carbonate pyridin bath until uniformly golden 

 brown. Care must be taken that the heating does not reach the 

 boiling-point by ceasing when steam reaches the surface. Rapidly 

 wash in distilled water and place in 20 per cent, neutral formol, 

 one minute after which fixation is carried out in a 20 per cent, 

 neutral solution of formaldehyde for one minute, followed by 

 fixation in 2 per cent. NagSoOg for a half to one minute. Wash 

 thoroughly two to three days in tap-water to which a little neutral 

 formaldehyde may be added. Then 95 per cent, alcohol, carbol 

 xylol and balsam. 



The silver carbonate pyridin bath is 

 10 per cent. AgNOg, 30 c.c. 

 Sat. aqueous, L^COg, 30 c.c. 



Wash precipitate several times in doubly distilled water, 



