GOLGI METHODS 517 



parts of 10 per cent, formalin and sulphuretted hydrogen. After 

 a few minutes the first discoloured portion of this mixture is 

 poured off and replaced with fresh solution, in which pieces remain 

 for another five days. They are then gradually dehydrated and 

 imbedded in cclloidin. Sections are cleared in carbol-xylol 

 (1:1) and mounted in balsam under a cover. Nerve-cells and 

 nerve-fibres are extensively impregnated. 



Corning {Anat. Anz., xvii, 1900, p. 108) hardens the tissues 

 in 10 per cent, formalin and then brings them into the lead formiate 

 which he buys from Merk. He prefers to cut without imbedding. 



1047. Wolter's Chloride of Vanadium Process {Ztschr. wiss. 

 Mikr., vii, 1891, p. 471). Central or peripheral nervous tissues 

 are fixed in Kultsehitzky's solution, followed by alcohol as 

 described in § 56. Celloidin sections, 5 to 10 /x thick, are mor- 

 danted for twenty-four hours in a mixture of 2 parts of 10 per 

 cent, vanadium chloride and 8 parts of 8 per cent, aluminium 

 acetate. They are then washed for ten minutes in water, stained 

 for twenty-four hours in an incubator in Kultsehitzky's haema- 

 toxylin, and differentiated in 80 per cent, alcohol acidified with 

 0-5 per cent, of hydrochloric acid until slightly blue-red. The acid 

 is then removed by washing with pure alcohol, and the sections 

 dehydrated, cleared with origanum oil, and mounted in balsam. 

 Axis-cylinders, nerve-cells and glia cells are stained, the myelin 

 being coloured only when the differentiation in the acid alcohol 

 has been insufficient. 



1048. Azoulay's Ammonium Vanadate Process {Bull. Soc. 

 Anat., Paris, Ixix, 1894, 5th S., p. 924). Wash in water thin 

 sections of material fixed in a bichromate solution and imbedded 

 in celloidin. Lift a section on a slide and pour on it a few drops 

 of 0-5 per cent, ammonium vanadate, wait a moment, pour off 

 the stain, wash with a little distilled water and pour on the section 

 a few drops of 2-5 per cent, tannin. After a few minutes pour 

 off the tannin solution, wash, and start all over again, and so on 

 until axis-cylinder and nerve-cells are stained dark green. Wash 

 quickly, dehydrate and mount. These preparations photograph 

 well. 



1049. Fajerstajn's Haematoxylin {Poln. Arch. Biol. Med. 

 Wiss., i, 1901, p. 189). Make sections, by means of the freezing 

 microtome, of material fixed for two to seven days in 5 to 10 per 

 cent, formalin. Transfer them into 0-25 to 0-5 per cent, chromic 

 acid, and after twenty-four hours wash them well, and put them 

 to stain for another twenty-four hours in 1 per cent, aqueous 

 solution of haematoxylin. Differentiate by Pal's method. 



1050. Nabias' Method (C. R. Soc. Biol, Ivi, 1904, p. 426). 

 Sections of material fixed in alcohol-corrosive sublimate or any 

 other fixing agent easily allowing the penetration of iodine are 

 treated until yellow with Lugol's solution (Gram's fornmla). 



