Tue Microscops. a13 
alcohol, glycerine and water. Sections also may be stored in 
this mixture. Nearly all vegetable sections require bleaching 
before being stained; very delicate tissues may be bleached by 
means of alcohol—hard and deeply-colored stems and woods 
must be bleached in a liquid thus prepared :— 
To one pint of water add two ounces of fresh chloride of 
lime; shake this up thoroughly two or three times, and allow it 
to stand until the lime shall have settled. Make a saturated 
solution of common “ washing soda.” Pour off the supernatent 
fluid from the chloride of lime, and, by degrees, add to it the 
soda solution, until all precipitation ceases. Filter the solution, 
and keep it in a stoppered bottle, in the dark. No fixed time 
can be given for the bleaching process, the color and density of 
tissues being so variable. Experience, however, will be rapidly 
gained, and over-bleaching easily avoided. The sections being 
bleached, must. now be washed in distilled water, several times 
changed, and allowed to remain for twenty-four hours in the 
final water, to which add 8 or 10 drops of nitric acid to each 
half-pint. Transfer the sections to alcohol, for an hour before 
staining them. To bring out details of structure and to display 
cell walls, &c., there is no better stain than Logwood, and for 
singly stained vegetable sections it is to be recommended in 
preference to all other staining fluids. The following process 
will give admirable results :— 
1st. Remove the section from alcohol to water for a few 
minutes. 
2d. To3 per cent. alum solution for ten minutes. 
3d. Stain in aqueous logwood stain. 
4th. Place in alum water to remove stain from surface. 
5th. Wash thoroughly in water. 
6th. Place in alcohol for two or more hours. Float the 
section lightly on the surface of oil of cloves; when it sinks it 
is ready to be mounted in Balsam. 
TO DOUBLE STAIN VEGETABLE SECTIONS. — 
1st. Place the section in an alcoholic solution of Iodine 
Green (3 grains to the one ounce of alcohol) for one or two 
hours. 
