GENERAL STAINS. 395 



as ammonia-carmine, but gives a better demonstration of non-nervous 

 elements. 



Chromic objects stain very slowly in both these media. Sections may, 

 however, be stained with them in a few minutes if they be put into a watch- 

 glass with the stain, and the whole be kept on a wire-net over a water-bath 

 heated to boiling-point (OBEBSTEINEB). See also 163. 



746. HENLE (Handb. d. Nervenlehre, 1871) gives the following, after 

 MEBKEL. In order to do away with the slowness of staining of tissues 

 hardened in chromates, sections should be placed in solution of chloride of 

 palladium (1 in 300 to 1 in 600) till they are of a straw colour (one or two 

 minutes), rinsed in water, and stained in strong ammonia-carmine. Myelin, 

 yellow ; axis-cylinders, nerve-cells, and neuroglia, deep red. 



747. SCHMAUS (Munch, med. Wochenschr., 1891, No. 8 ; see Zeit. f. 

 wiss. Mik., viii, 2, 1891, p. 230, and Journ. Boy. Mic. Soc., 1892, p. 439) 

 obtains a ground-stain and axis-cylinder stain by means of a uranium 

 soda-carmine solution. 



748. UPSON (Neurolog. Centralb., 1888, p. 319 ; Zeit. f. wiss. Mik., v, 

 4, 1888, p. 525) employs a stain made by adding to 5 c.c. of strong Gren- 

 acher's alum-carmine 1 to 3 drops of phospho-rnolybdenic acid. In this, 

 sections stain in from two to ten minutes. 



He also employs a stain made by saturating alum-carmine with zinc 

 sulphate. Sections stain in this in from half an hour to twelve hours. 

 This is said to give very good differentiations of the elements of peripheral 

 nerves. 



A third method of the same author consists in staining with carminic acid, 

 and afterwards treating with a mordant. See the papers quoted. 



FBEEBORX (Amer. Mon. Mic. Journ., 1888, p. 231 ; Journ. Roy. Mic. 

 Soc., 1889, p. 305) also recommends carminic acid, followed by treatment 

 with 10 per cent, solution of chloride of iron. 



749. Borax-carmine may be used. It is chiefly useful when employed 

 for double-staining with indigo-carmine or an anilin blue to follow. I have 

 obtained some superb stains with Seller's borax-carmine and indigo-carmine 

 process ( 241). MEBKEL'S mixture of borax-carmine and indigo-carmine 

 ( 242) has been strongly recommended by MAX ELESCH (Zeit. f. wiss. Mik., 

 1884, p. 566, and 1885, p. 349), who says that it gives extremely rich and 

 instructive images. 



DUVAL (Journ. de I'Anat., 1876) speaks very highly of the double-stain 

 quoted ante, 243. 



750. Alum-carmine (Grenadier's or Csokor's) may be used as a nuclear 

 stain (OBERSTEINER). The stain principally takes effect on non-nervous 

 nuclei. 



751. KEHM (Munch, med. Wochenschr., 1892, No. 13 ; Zeit. f. wiss. Mik., 

 ix, 3, 1893, p. 389) gives the following: Sections (of alcohol-hardened 

 material) stained for five minutes in 1 per cent, ammonia-carmine, and 

 washed out in 70 per cent, alcohol acidified with 1 per cent of nitric acid ; 

 the acid removed by pure alcohol ; the sections stained for half a minute 



