34:2 The Microscope. 



follow those results. Accordingly, I would like to describe the 

 method employed in this laboratory (Zurich) ; for, although it has 

 been mentioned by Professer Gaule in his lectures for several 

 years, it has not as yet been published. 



The methods formerly used were that of examining fresh blood 

 and that, perfected by Ehrlich, which consisted in staining dried 

 blood. 



Our method consists in a series of manipulations requiring only 

 thirty-five minutes for their completion. 



The following is a list of the reagents, together with the length 

 of time and the order in which each is to be used: 



Min. 



1. Corrosive sublimate (concentrated solution ) 6 



2. Distilled water 1 



8. Absolute alcohol 5 



4. Distilled water 1 



5. Hsematoxylin {^ per cent, alum solution to which, for 



every 100 c.cm. employed, 20 drops 5 per cent, 



alcoholic solution have been added) 6 



6. Distilled water 1 



7. Nigrosin {^ per cent, water solution) 1 



8. Distilled water ^ 



9. Eosin (1 gr. eosin dissolved in GO c.cm. alcohol; 140 



c.cm. distilled water) 2 



10. Alcohol 5 



11. Oil of cloves 1-2 



12. Xylol. 



13. Canada balsam (diluted with xylol until it flows readily). 



As receptacles for these fluids, each person has upon his table 

 three shallow glass dishes with flat bottoms, so large that a slide may 

 be easily put in and taken out of them. Into the first of these we 

 pour corrosive sublimate, into the second distilled water, and into the 

 third absolute alcohol. It is necessary either to label the dishes or 

 to place the two not at the moment in use at one side. For the 

 coloring -fluids we use bottles whose stoppers serve at the same time 

 as droppers or pipettes. The most convenient form has a glass stop- 

 per, which is hollow and drawn out into a fine point below, while above 

 it broadens into a funnel with a lip whose opening is closed by 

 a rubber membrane. A slight pressure upon the membrane causes, 

 upon the removal of the finger, a rise of fluid in the funnel, which, 

 upon the removal of the stopper from the bottle, can be at pleasure 



