96 METHODS OF MICROSCOPICAL RESEARCH. 



clearing agent under the sections, letting them sink 

 through alcohol into the clearing agent placed at 

 the bottom of a test tube or saucer, with alcohol 

 above it, raising the sections with " lifters," &c., 

 but this complicated process tends to the destruc- 

 tion of the sections, which cannot be too little 

 manipulated. Now, in xylol and phenol we have 

 a medium which requires no such treatment, all 

 that is necessary being to place the fluid in a saucer 

 to the depth of about a quarter of an inch. The 

 saucer should be a large one, so that there shall be 

 no difficulty in removing the sections, or any 

 necessity for dragging them up the side of the 

 saucer. Place the sections for five minutes in 

 absolute alcohol, transfer them, with a thick curved 

 needle which has a blunt point, to the surface of the 

 clearing fluid. The alcohol is almost instantly 

 removed and the sections sink to the bottom. Then 

 take a perfectly clean cover, and with the curved 

 needle float a section carefully on to the cover and 

 spread it perfectly flat, drain 'the excess of the fluid 

 on to a piece of blotting paper, by holding the cover 

 in forceps and placing its edge upon the blotting 

 paper, then lay the cover section upwards upon the 

 blotting paper to remove the clearing fluid from its 

 under surface, and before the clearing fluid evaporates 

 apply xylol balsam to the section. The balsam 

 being miscible with the clearing fluid, there is 

 nothing antagonistic or greasy to remove, which is 

 the case when oil or turpentine, or both, are em- 

 ployed as clearing agents. 



This medium is the best that can be used for 

 clearing sections cut from specimens which have 

 been embedded in celloidin, upon which it has no 

 solvent effect. 



