STAINING METHODS. 2if 



As the section is put in the dye, care should be taken to so float it 

 out that it may not be curled. This is easily done with the needle. 

 After the alcohol bath, however, this becomes difficult, as the tissue 

 is rendered stiff by the removal of the water. 



This is the simplest and best of all methods for general work, and 

 you are advised to master every detail of the process. After reading 

 the directions which I have given, and having never seen the work 

 actually done, you will not be singular if you conclude the staining 

 of tissues to be a tedious and slow process; but after a month's work 

 you will be able to stain fifty different sections in half an hour, and 

 have them ready for mounting. 



H^MATOXYLIN AND EOSIN. DOUBLE STAINING. 



Very beautiful and valuable results in differentiation are obtained 

 by staining first with hasma. and subsequently with eosin. Eosin is a 

 salt of resorcin, staining most animal tissues pink, and it affords with 

 the haema. a good contrasting color. The tissue is to be stained in 

 haema. and washed in water as usual; then it is placed in the eosin 

 solution, and afterwards washed again. The subsequent treatment 

 is as with the plain haema. process, viz., dehydration with alcohol, 

 after which the oil of cloves. 



FIG. 15. DIAGRAM INDICATING THE SUCCESSIVE STEPS IN DOUBLE STAINING WITH 



. AND EOSIN. 



The diagram, Fig. 15, shows the process complete: 



1. Watch-glass with haema. 



2. Saucer with water. 



3. Watch-glass two- thirds filled with water, witli five drops of eosin 

 solution added. 



4. Saucer containing water. 



5. Salt-cellar filled with alcohol. 



6. Covered oil-dish. 



The eosin stains very quickly, generally in about a minute. Care 

 should be taken not to overstain with it, as it cannot be washed out. 

 If the sections are found at any time to be overstained with haema. 

 the color may be removed to any desired extent by floating them in a 



