THE PARAFFIN METHOD 
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this first pouring cannot be used again. Now flood the slide several 
times with the turpentine or xylol, pouring the reagent back into 
the bottle. 
REMOVAL OF XYLOL OR TURPENTINE 
To remove the xylol, place the slide in equal parts of xylol and 
absolute alcohol in a Stender dish. After 5 minutes, transfer to 
absolute alcohol, which should also be allowed to act for 5 minutes. 
If the pouring process is preferred and turpentine has been used 
to remove the paraffin, remove the turpentine by flooding the slide 
with 95 per cent alcohol. About 100 c.c. of turpentine and 200 c.c. 
of 95 per cent alcohol should be sufficient for 50 slides, even if the 
sections are to be mounted under the longest covers. By keeping 
both reagents in bottles and pouring the liquid on the slide, the 
reagents are always fresh. A given quantity of the reagent will 
prepare as many slides by one method as by the other. 
TRANSFER TO THE STAIN 
After the paraffin has been removed with xylol or turpentine, 
and the xylol or turpentine has been rinsed off with alcohol, the next 
step is the staining. If the stain is a strong alcoholic one (85 to 100 
per cent alcohol), transfer directly to the stain. If the stain is in 
70 per cent alcohol, pass through 95 and 85 per cent alcohol, 2 minutes 
in each, before staining. If an aqueous stain is to be used, pass down 
the whole series—95, 85, 70, 50, 35, and water—2 minutes in each, 
before placing the slide in the stain. 
This is rather tedious, but, for cytological work, it seems to be 
necessary. For general morphological work, the slide may be 
transferred directly from the absolute or 95 per cent alcohol to any 
stain. 
DEHYDRATING 
After the sections have been stained, they must be dehydrated. 
If they have been stained in a strong alcoholic solution, transfer to 
95 and then to 100 per cent alcohol, 2 minutes in each, if the stain 
does not wash out too rapidly. If stained in an aqueous solution, 
pass-through the series, water, 35, 50, 70, 85, 95, and 100 per cent 
alcohol, about 2 minutes in each. 
With stains which wash out rapidly, the times must be shortened 
and some of the alcohols must be omitted. With aqueous gentian- 
violet, all must be omitted except the 95 and 100 per cent, and even 
in these the time must be shortened to a few seconds. 
