XXXIV- INTBODUCTION. 



slide, and press them down gently with the finger. Warm 

 gently in an oven or over a flame till the parafiSn is just 

 melted, and immerse the slide in turpentine for two or three 

 ininutes to dissolve out the paraffin from the sections. Lift 

 the slide out of the turpentine, drain and remove the excess of 

 turpentine with a duster, place a drop of balsam over the 

 sections while still moist with turpentine, and cover. In the 

 case of sections stained with bsematoxylin it is advisable, 

 after removing the excess of turpentine, as described above, to 

 run oil of cedar-wood over the sectioBS in order to completely 

 remove the turpentine, which tends to osidise and decolourise 

 haamatoxylin, and thus destroys the stain. 



In some cases it is necessary to stain sections on the slide. 

 The following is a conTenient method : Fix the section with 

 glycerin and albumen, aud remove the paraffin by warming 

 the slide and placing it in turpentine as described above. 

 AVhen the paraffin is all dissolved out, place the slide in 

 absolute alcohol few a few nrinutes to remove the turpentine. 

 Then pass the slide gradually through 90 per cent., 70 per 

 cent., 50 per cent, alcohol. If an alcoholic stain (e.g. borax 

 carmine, alcoholic safr&nin, etc.) is to be used, the slide is now 

 placed in stain. If an aqueous stain (cgr. hsemalum, etc.) is 

 to be used, the slide must be plaioed in 30 per cent, alcohol, 

 then in water, and then into stain. After being in stain the 

 requisite amount of time, the excess of stain is removed by 

 washing in some suitable reagent, and: the slide is then 

 passed gradnally through 50 per cent., 70 per cent., 90 per 

 cent, to absolute aleohal, where it is allowed to remain a few 

 minutes in order to thoroughly debydirate. After dehydration 

 oil of cedar- wood is poured over the sections till the alcohol 

 is all removed and the oil flows> freely over the slide. The 

 excess of oil is then removed, balsam placed on the sections, 

 and they are covered in the usual way. 



Curled or crumpled sections shouldl be straightened before 

 mounting, so that all the parts of the object lie in one plane. 

 This can be done as follows : Smear the slide with glycerin 

 and albumen, and place a few drops of clean (or distilled) 

 water on the slide. Place the crumpled sections on the 



