136 THE AMERICAN MONTHLY [April 



8. Concentrated spirituons solution of picric acid, 2 

 minutes. 



9. Absolute alcohol, oil, balsam, 



Elastiu, orcein, brown; collagen, acid-fuchsin, red: 

 muscles, protoplasm, yellow ; nuclei, grey-violet. 



(e) Acid Orcein-Methylene Bhte-Permanganate of 

 Potassium Acid- Alcohol Method. 



1. Acid orcein solution, 10 minutes while beingheated. 



2. Wash in dilute spirits. 



3. Water. 



4. Polychrome methylene-blue solution, 10 minutes 



5. Water. 



6. 1 per cent solution of permanganate, 10 minutes. 



7. Water. 



8. Acid alcohol, 10 minutes. 



9. Water. 



10. Absolute alcohol, oil, balsam. 



Elastin, orcein, brown ; collagen, decolorized ; muscle, 

 protoplasm, nuclei, violet. — St. Louis Medical Journal. 



A New Way of Marking Objectives. 



WILLIAM C. KRAUSS, M. D., F. R. M. S. 

 Secretary of American Microscopical Society. 



BUFFALO, N. Y. 



That every microscopist in demonstrating to his classes 

 in histology or pathology has been annoyed in determin- 

 ing the focus of the various objectives when a nose-piece 

 is used, no one will dare contradict. The small letters 

 or figures, designating the focus, engraved on the body 

 of the objective have often to be sought for with great 

 vexation, necessitating at times the removal of the lens 

 from the nose-piece, or in revolving the lens or nose- 

 piece so that the number will be discernable. Sometimes 



