130 THE AMERICAN MONTHLY [June, 



wood into a vessel, pour on the alum solution and let stand for forty- 

 eight hours. Strain through muslin and add four ounces of glycerine 

 and one ounce of rectified spirit, mix well together, filter through paper, 

 and add a small lump of camphor to make the mixture keep. 



Add from 30 to 40 drops of logwood solution to one once of distilled 

 water, filter and immerse the sections three or four hours. Wash well 

 in distilled water and then soak for a short time in ordinary tap water 

 to fix the color. 



Transfer to methylated spirit or alcohol for ten or fifteen minutes to 

 dehydrate. Take a small saucer or watch-glass full of clove oil and 

 carefully float the section on the surface of the oil, and let it soak for 

 five or ten minutes. When quite clear, wash in turpentine and mount 

 in Canada balsam. The logwood solution may be used undiluted for 

 quick staining, but better results are obtained by the slower pro- 

 cess. 



Mounting in Canada Balsam. — Take 4 ounces of dried Canada 

 balsam and dissolve in 4 fluid ounces of benzole, filter, and keep in a 

 good outside-capped bottle. Clean a slide, place some balsam on its 

 centre, take the section from the turpentine with a lifter, and place it in 

 the balsam on the slide. Now clean a cover-glass, and with a pair of 

 forceps bring its edge in contact with the balsam on the slide ; ease it 

 down carefully so that no air bubbles may be enclosed, and press down 

 until the section lies quite flat. Now put the slide away for a day or 

 two so that the balsam may set, and then take a soft brush and with 

 some benzole wash away the exuded balsam from round the edges of 

 the cover. Allow the slide to dry and apply a good coat of gold size, 

 and when this has dried, wash the slide with some soap and water ; dry 

 well with a soft cloth and add a coat of asphalt. 



Double Staining. (Anilin Acid Green Stains.) — ^Take of acid 

 green 2 grs., of distilled water 3 ozs., and glycerine i oz. Mix the 

 water and glycerine well together, and dissolve the green in the mixt- 

 ure. 



Carmine Stain. — (A) Of borax 10 grs., distilled water i oz., gly- 

 cerine ^ oz., alcohol ^ oz. Dissolve the borax in water and add the 

 glycerine and alcohol. 



(B) Carmine 10 grs., liquor ammonia 30 mins., distilled water 30 

 mins. Dissolve the carmine in the ammonia in a test tube, with the 

 aid of heat, if necessary, and add the water. Mix A and B together 

 and filter. 



Place the section in the green stain for five to ten minutes. Wash 

 well in distilled water. Place in the carmine stain for ten to fifteen 

 minutes, and wash in spirit in which the section must remain for at 

 least ten minutes. Clear in clove oil and mount in Canada bal- 

 sam. 



Mounting Sections in Glycerine Jelly. — Place the section in dis- 

 tilled water and soak until all trace of alcohol is removed. Warm the 

 jelly and place a few drops on the centre of a clean slide, and put the 

 section in it. Clean a cover glass and apply it in the same way as di 

 rected for balsam. Allow the slide to cool, and then the exuded jelly 

 may be scraped away with a penknife, and the slide washed with water. 

 Dry well with a soft rag and apply a coat of gold size, and when this 

 has dried, add another of asphalt. 



