Essentials of bacteriology; being a concise and systematic introduction to the study of bacteria and allied microörganisms . s (Fig. 13). It prevents theflame or staining fluid from reaching the fingers. The object is now ready for staining. Staining.—^A few drops of the staining solution are placed GENERAL METHOD OF STAINING SPECIMENS 55 upon the cover-glass so that the whole specimen is covered,and the stain is left on a few minutes, the time dependingupon the variety, the strength of stain, and the object de-sired. Instead of placing the dye upon the object, the cover-glass can be immersed
Essentials of bacteriology; being a concise and systematic introduction to the study of bacteria and allied microörganisms . s (Fig. 13). It prevents theflame or staining fluid from reaching the fingers. The object is now ready for staining. Staining.—^A few drops of the staining solution are placed GENERAL METHOD OF STAINING SPECIMENS 55 upon the cover-glass so that the whole specimen is covered,and the stain is left on a few minutes, the time dependingupon the variety, the strength of stain, and the object de-sired. Instead of placing the dye upon the object, the cover-glass can be immersed in a small glass dish containing thesolution; or, if heat is desired to intensify or hasten the proc-ess, a watch-crystal holding the stain is placed over a Bun-sen burner and in it the cover-glass; the cover-glass may beheld directly in the flame with the staining fluid upon it,which must be constantly renewed until the process is com-pleted, or the cover-glass can be heated in a test-tube, con-taining stain solution. Removing Excess of Stain.—The surplus stain is washedoff by dipping the glass in distilled Fig. 13.—^Authors bent forceps for holding cover-glass over iiame. The water is removed by drying between filter-paper orsimply allowed to run off by standing the cover-glass slant-wise against an object. When the specimen is to be examinedin water (which is always best with the first preparation ofthe specimen, as the Canada balsam destroys to some extentthe natural appearance of the bacteria), a small drop of ster-ilized water is placed upon the glass shde, and the cover-glassdropped gently down upon it, so that the cover-glass remainsadherent to the slide. The dry system or the oil immersion can now be used. When the object has been sufficiently examined, it can bepermanently mounted by Ufting the cover-glass off the sHde(this is facilitated by letting a Httle water flow under it, one 56 ESSENTIALS OF BACTERIOLOGY end being slightly elevated). The water t
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisherphila, bookyear1913
