1895.] MICROSCOPICAL JOURNAL. 197 



Microscopical Technique Applied to Histology. — IX. 



[FROM THE FRENCH OF RENE BONEVAI..] 



(Continued fro7npage 344, November 1894.) 



Sections of the same nerve made after the action of 

 ammonia bichromate, gum and alcohol, should be differ- 

 ently stained. Some, to show the laminated sheaths 

 and the connective tissue of the nerves, should be stained 

 by hsBmatoxylin and eosine, and mounted in balsam 

 after dehydration and clearing by oil of bergamot. 

 Others should be stained by Weigert's method, which 

 specially stains myeline. Follow carefully these direc- 

 tions : 



Sections are made from the nerve fixed and hardened 

 by ammonia bichromate until it is brown, not green, and 

 kept for a long time in alcohol. For 24 hours leave the 

 sections in some of the following solution in a warm 

 place : saturated solution of acetate of copper, 20 ; fil- 

 tered water, 20. Remove them to Weigert's hajmatoxy- 

 lin raised to 35° or 40° C. (hsematoxylin, 1 part ; alcohol, 

 10 parts ; water, 90 parts ; saturated solution of carbon- 

 ate of lithia, 1 part). When stained (in about 4 hours), 

 wash in water and transfer to the following solution: 

 borax, 2 grms. ; red prussiate of potash, 2.50 grms. ; 

 water, 20 grms. Leave them here for from one-half to 

 one hour. It is well to ascertain the degree of colora- 

 tion with a low power. Wash in water, mount in 

 balsam. 



To study by sections the fibres without myeline, cut 

 transverse sections of the pneumogastric of the frog, the 

 rabbit or the dog, after fixing by osmic acid, hardening 

 by alcohol and gum ; stain in alum carmine, mount in 

 glycerine. 



SPINAL CORD. 



Nerve Cells. — A piece of the spinal cord of the ox, 



