464 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Can be united with a mixture of turpentine and absolute alcobol (in 

 equal parts ?), and in this form used for staining sections. 



The method of using these stains is very simple. The sections are 

 fastened to the slide by Schallibaum's collodion, then left in the oven of 

 the water-bath until the clove oil has been completely driven off. The 

 paraffin is next removed by washing in turpentine, and then the slide is 

 immersed in the staining mixture. As soon as the desired depth of stain 

 has been received, the sections may be washed in pure turpentine and 

 mounted in balsam. 



If the stain is too deep, or a sharp nuclear stain is desired, it is only 

 necessary to leave the slide a short time in a mixture of turpentine and 

 pure (free from any trace of acid) absolute alcohol, and the colour will 

 be reduced. 



The colouring mixture may become cloudy, as the result of the 

 evaporation of the alcohol ; in such an event, the addition of a drop or 

 two of alcohol generally suffices to clear the mixture. 



This method enables one to use easily several stains in succession. 

 Objects may also be coloured, in toto, with the advantage that the process 

 of staining can be followed and easily controlled. 



Double, Triple, and Quadruple Staining.* — Dr. H. Griesbach 

 demonstrated at the meeting of the Anatomical Society held at Wiirzburg 

 the following methods of staining. The dyes used were anilins in con- 

 centrated aqueous solutions either in combination, or as single successive 

 stains. The stained specimens were cleared in anise oil, and mounted 

 in balsam. 



Double Stains. — Metanil yellow [phenylamidobenzolmetasulphonate 

 of soda], and azoblue [tetraazoditolylbetanaphtholdisulphonate of soda]. 

 Preparation : ala nasi of a child, alcohol hardening. 



The sections are stained in a mixture of equal parts of the two 

 staining fluids for 10 minutes, or for 10 minutes in the yellow fluid, and 

 then for four minutes in the blue. 



The epidermis, hair-shaft, inner root-sheath, striated and smooth 

 muscle stain yellow ; the rete Malpighii, the outer root-sheath, sebaceous 

 and sweat glands stain brownish-yellow ; connective tissue, elastic fibres, 

 and membrane of fat-cell stain violet-blue ; hyaline cartilage and nuclei 

 do not stain. 



Metanil-yellow and methyl- green.— Preparation : ala nasi of a child, 

 alcohol hardening. 



The sections are stained in a mixture of 5 ccm. of the yellow staining 

 fluid, and 3 ccm. of the green. A crystalline precipitate forms which 

 does not interfere with the staining. The sections are allowed to remain 

 in this fluid for eight minutes or longer [1/4 of an hour], or they are 

 stained for eight minutes in the yellow fluid, and then for one minute in 

 the green. 



Epidermis, hair-shaft, inner root-sheath, striated and smooth muscle 

 stain yellow ; the rete Malpighii, outer root-sheath, hair follicle, sweat 

 and sebaceous glands, and nuclei stain green ; hyaline cartilage and cells 

 stain green. 



Metanil-yellow and crystal violet [Hydrochloride of hexamethyl- 

 pararosaniline]. — Preparation : ala nasi of child, alcohol hardening. 



Mix 7 ccm. of the yellow fluid with 2 ccm. of the violet. An amorphous 



* Amer. Mou. Micr. Journ., x. (1889) pp. 30-3. 



