REAGENTS AND STAINS. 203 



(3) When dry pass the cover-glass three times 

 through a flame, keeping the preparation up. 



(4) Apply stain. 



(5) Wash in distilled water by dipping the covier- 



glass in the water two or three times. 



(6) Examine as a water mount or, if desired, dry 

 and mount in balsam. 



(7) Label and lay aside in a horizontal position until 

 balsam hardens. 



Note. The above method may be used for all sim- 

 ple staining. Special methods, however, are often used* 

 and they will be given as required. 



LABORATORY EXERCISE;. Centering and labeling. 

 Upon the under side of your box-cover make an 

 outline of a slide. The pencil should have a needle 

 point. Connect opposite angles and place over the in- 

 tersection of the lines a cover-glass. Be sure that the 

 centre of the cover-glass coincides with the center of 

 the diagram. Now, carefully make an outline of the 

 cover-glass. This outline may be used for centering 

 both the sections and the cover-glass. Make a draw- 

 ing of this outline and also a drawing of a 

 slide with labels and cover-glass in situ. Fill in the 

 forms of labels in second diagram, using the following 

 data : A transverse section of the muscle of a normal 



