90 Modern Microscopy. 



(4) Put away out of the reach of dust for twelve hours, 

 to allow the benzine to evaporate from the balsam. 



(5) Warm a slide over a spirit-lamp and apply a drop of 

 balsam to that on the cover-glass ; take it up with a pair 

 of forceps, and bring the drop of fluid balsam in contact 

 with the centre of the warmed slide. Ease the cover down 

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

 it down with the point of the forceps until the section lies 

 quite flat and the excess of balsam is squeezed out. Now 

 allow the slide to cool ; the excess of balsam may then be 

 washed away with some methylated spirit and a soft rag. 



Eosin Stain. Useful for sieve-tubes and plates. Make 

 a strong solution of eosin in equal parts of water and 

 alcohol, and stain the section for five to ten minutes. 

 Wash well in methylated spirit, dehydrate, clear in clove 

 oil, and mount in Canada balsam. 



LESSON 8. 



THE PREPARATION OF VEGETABLE TISSUES 

 FOR MOUNTING IN GLYCERINE JELLY, 

 ACETATE OF COPPER SOLUTION, ETC. 



Epidermal Tissues for Stomata. Get some leaves, 

 cut them into small pieces, and place them in a jar of 

 water, in which they must remain for several weeks, or 

 until the cellular tissue rots and the epidermis is set free. 

 Wash well in water, stain in a watery solution of methyl 

 violet, and mount in glycerine jelly. 



Annular Vessels. Get some stem of maize, cut it into 

 pieces about half an inch long, and then cut again into 

 thin longitudinal slices ; place these in water until rotten. 

 Now put some of the broken-up material on a slide and 

 examine with a microscope ; pick out the annular vessels 

 on the point of a needle, place them in some clean water, 

 and wash well. Stain in a weak watery solution of acid 



