314 



STAINING AND PERMANENT MOUNTING [ CH. X 



not safe. A safe method for all objects is to add a slight weight, 

 and put the slide in a warm place. 



After the balsam is quite dry the excess may be scraped off the 

 slide with a knife and then the slide and cover cleaned from the 

 remaining balsam by a piece of gauze wet with xylene. Finally the 

 slide should be labeled and stored. 



FlG. 252. Coplin's staining dish. 

 A. The entire dish; B. The dish in 

 cross section. This is made of glass and 

 is a very neat piece of apparatus. With 

 it ten slides may be stained at once. 

 (Cut loaned by the Whitall Tatum Co.) 



CROSS-SECTION 

 SHDV/ING SLIDES 

 IN POSITION. 



466. Counterstaining with the Eosin in the Clearer. 

 With this method the eosin is dissolved in the carbol-xylene clearer, 

 and the hematoxylin stained sections are dehydrated with 95% 

 alcohol and absolute alcohol if necessary and then placed in the 

 clearer. The sections are cleared and stained in eosin at the same 

 time. It usually takes half a minute or more for the double process. 

 When the sections are clear and sufficiently red, the slide is removed 

 and the clearer drained off by holding in the forceps or in the drain- 

 ing funnel (Figs. 248, 251). Then the balsam is added, and cov- 

 ered as described above. 



It is a good plan to rinse off the stained clearer by pure xylene 

 before adding the balsam. This is not absolutely necessary, how- 

 ,ever. 



467. Hematoxylin and Picro-Fuchsin. Picro-fuchsin is 

 so selective in its general staining that it is frequently used after 

 hematoxylin. The hematoxylin staining should be intense and 

 after the hematoxylin is washed away add the picro-fuchsin ( 424). 

 It takes only a few seconds for it to act, 10 to 30 seconds. Wash 

 with distilled water, or natural water very faintly acidulated. The 

 acid fuchsin is very sensitive to alkalies and fades easily. 



