758 HISTOLOGIC TECHNIC 



11. Dry with blotting paper, drop in absolute alcohol, pass 

 through bergamot oil into xylol and mount in balsam. 



According to Wildman (Jour. Morph., 24, 3, 1913) the slides may 

 be passed from the alizarin solution, after rinsing, 1, into a 3 per cent, 

 solution of crystal violet (3 c.c. anilin stain in 100 c.c. distilled water) 

 for ten minutes; 2, rinse and place in 80 per cent, alcohol for five sec- 

 onds; 3, pass through 95 per cent, and 100 per cent, alcohol, where the 

 differentiation is watched; 4, clear and mount in the usual way. 



Zimmermann's Technic, for demonstrating the intercalated disks 

 of cardiac muscle. 



1. Small pieces of tissue are fixed for twenty-four hours in a solu- 

 tion of 90 parts absolute alcohol and 10 parts 25 per cent, nitric acid. 



2. Wash in several changes of 95 per cent, alcohol, or until it re- 

 mains neutral to litmus paper. 



3. Pass through graded alcohols to distilled water. 



"4. Transfer to solution of 1 gram hemalum (Griibler's) to 10 c.c. 

 water, where it remains for eight to ten days. 



-5. Wash in distilled water, embed in paraffin, and section. 



The intercalated disks are conspicuously stained a dark blue, which 

 contrasts sharply with the light-blue background. 



These disks can be well demonstrated also by fixation in Carnoy's 

 fluid, followed by irou-hematoxylin stain. For the same purpose Heiden- 

 hain employs vanadium hematoxylin after sublimate fixation (see Lee's 

 Vade Mecum). 



Gage's Method, for Demonstrating Glycogen. Glycogeu granules 

 are readily soluble in aqueous media. Tissue which is to be tested for 

 this substance should be fixed in 95 per cent, alcohol. 



1. Embed in paraffin in the usual way. 



2. Flatten sections on slide by use of the following iodin solution 



(Lugol's solution), which is subsequently used for staining: 



Iodin 1.5 grm. 



Potassium iodid 3.0 grm. 



Sodium chlorid 1.5 grm. 



50 per cent, alcohol 300 c.c. 



3. Stain, dehydrate, dissolve paraffin with xylol, mount in melted 



vaselin, and seal cover glass with shellac. The glycogen grains 

 arc stained mahogany red. 

 Osmic Acid Technic for Fat. Free fats and lipoids are soluble in 



