Cutting, Staining, and Mounting Vegetable Sections 175 



natural shape. Then place in methylated spirit, which 

 must be changed every twenty-four hours for three days to 

 remove all the water. Then make sections in accordance 

 with instructions given for ordinary botanical specimens. 



Powdered Drugs. — Place some of the powder in 

 methylated spirit, and soak for an hour or two ; then pour 

 off the spirit, and add clove-oil ; let it stand a little while, 

 then drain off the oil, take up some of the powder on the 

 point of a knife, place it in some Canada balsam on a 

 cover-glass, mix it well up with the balsam, and then 

 proceed to mount it as directed for pollens. 



Mounting in Canada Balsam. — Take 3 ounces of dried 

 Canada balsam and dissolve in 3 fluid ounces of benzole. 

 Filter and keep in an outside stoppered bottle. 



(1) Clean a cover-glass, moisten the surface of a slide 

 with the breath, apply the cover-glass to it, and make sure 

 that it adheres. 



(2) Place a few drops of balsam on the cover-glass. 



(3) Take the section out of the turpentine on a lifter, and 

 put it into the balsam on the cover. 



(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. Allow 

 the slide to cool, and the excess of balsam may then be 

 washed away with some methylated spirit and a soft rag. 



