STAINS, REAGENTS, &c. 41 



specimen, which, must he examined at intervals, to ascertain the progress of 

 staining, and when deep enough in colour, the specimens should he rinsed in 

 two or three changes of alcohol. 



2. Place the specimen in Absolute alcohol and allow to stand for twelve hours 

 to thoroughly dehydrate them, and if they are large change the alcohol once or 

 twice during the interval. 



•3. Pour off the alcohol and cover the specimens with oil of cloves, allow to 

 stand until clarified. 



4. Transfer the specimens into thin halsam and henzol, and allow to stand 

 for several hours to free them from the oil of cloves. 



5. Mount the specimens in halsam in cavity slips, without pressure. 



Manipulation for the Second Filtrate. 

 Specimens or sections to he stained from water. 



1. Pour off the water and cover the specimens or sections with the stain, 

 allow to stand — in the case of sections, for fifteen to thirty minutes, — in the 

 case of specimens, one to three hoiirs according to their size and density. 

 Examine the specimens from time to time, and when deep enough in colour, 

 rinse in two or three changes of 25% alcohol. 



If the specimens are to be mounted in balsam they must be graduated to 

 92% alcohol, and then placed for several hours in absolute alcohol to thoroughly 

 dehydrate, and treated for mounting as described above for the first filtrate. 



If the specimens are too delicate to admit of mounting in balsam, prepare 

 them as follows for mounting in glycerine jelly. After staining and 

 dehydrating, place the specimens, first, into one part pure glycerine and two parts 

 92% alcohol; secondly, into equal parts of glycerine and alcohol; thirdly, into 

 pure glycerine ; allow the specimens to stand an hour or two in each. 



2. Mount the specimens in glycerine jelly. 



No. 3. HyEMATOXYLIN.— Kleinenberg (modified). 



Hsematoxylin 1 gram. 



Calcium chloride 8 grains, in 40 cc. of water. 



Alum 3 grams, in 60 cc. of water. 



Alcohol 92% 770 cc. 



