Ammonia liquid, ether, picro-lithium carmine, potash solution.
Safranine, concentrated alcoholic solution of, and a watery solution.
Turpentine, vesuvin, water distilled and sterilised.
Aqueous solutions of the several dyes may be kept in bottles ready for use.
To both aqueous and alcoholic solutions a few drops of phenol, or a crystal of thymol, should be added as a preservative. For the rapid staining of cover-glass preparations, it is convenient to have the most frequently used stains—fuchsine, methyl-violet, &c.—in bottles provided with pipette stoppers.
Clearing Agents.—Oils of cedar wood, cloves, origanum, aniline, terebene, toluol and xylol, benzol and spirits of turpentine.
Mounting Media.—Acetate of potash solution concentrated, benzole, balsam, glycerine jelly, Fanant’s medium, dammar and mastic, Canada balsam in xylol, Hollis’s glue, zinc white.
Cement for fixing small specimens temporarily to a glass slide. Remove all traces of moisture, place upon it a drop or two of a medium prepared as follows:—Dissolve over a water bath 15 grammes of white lac in 100 grammes of absolute alcohol, decant off the clear liquid, and stand it by for a while.
As the alcohol evaporates from the warmed surface of the glass slide a hard transparent coating is left. This may be slightly softened at any time by means of a drop of oil of lavender. After arranging the objects the heat of a spirit-lamp will cause the oil to evaporate, leaving them firmly attached. Objects may be mounted on cover-glasses in a similar way. A resinous mounting medium may then be employed in the usual manner. If glycerine or glycerine jelly is the mounting medium employed, collodion diluted with two or three times its volume of oil of lavender may be found preferable as the fixing agent. The section should be placed in position before the preparation dries and the oil is evaporated.
Methylated spirit is often so largely adulterated with rock-oil as to render it unsuitable for technical purposes. Even to varnishes it imparts a fluorescent appearance as it dries off.