170 Modern Microscopy 



(3) Take of hydrochloric acid 1 part, and of methylated 

 spirit 5 parts ; mix well together, and soak the section 

 until the colour changes to a bright scarlet, which takes 

 about five minutes. The acidulated spirit may be kept 

 ready for use at any time. 



(4) Wash well in methylated spirit. Then place in some 

 strong methylated spirit, and soak for at least ten minutes 

 to dehydrate. 



(5) Place the section on the surface of a small saucer of 

 clove-oil, and let it soak until clear. 



(6) Eemove from the clove-oil and place in turpentine, 

 and then mount in Canada balsam. 



Full instructions for mounting in Canada balsam are given 

 at end of lesson. 



Hsematoxylin. — Haematoxylin, 30 grains ; absolute 

 alcohol, 3 J ounces ; distilled water, 8 J ounces ; glycerine, 

 3 ounces ; ammonia alum, 30 grains ; glacial acetic acid 

 3 drams. Dissolve the haematoxylin in the alcohol and the 

 alum in the water ; then add the glycerine and acetic acid. 

 Mix the two solutions together, and let the mixture stand 

 for at least a month before use. 



(1) Add about 30 drops of the above to an ounce of dis- 

 tilled water, and stain the section for fifteen to thirty 

 minutes. 



(2) Wash well in distilled water, and then in ordinary 

 tap-water. This will fix the colour and make it deeper. 



(3) Dehydrate in strong methylated spirit for at least 

 ten minutes. 



(4) Clear in clove-oil and mount in Canada balsam. 

 Double Staining — Dalton Smith's Method. — Stems, 



roots and leaves : 



Green Stain. — Acid aniline green ... 2 grains. 

 Distilled water ... 3 ounces. 

 Glycerine ... ... 1 ounce. 



Mix the water and glycerine together, and dissolve the 

 green in the mixture. 



