THE MICROSCOPE. 73 



shifted to one side or the other according as the fine motion screw 



was turned up or down. For the use of most of the instruments 



above named I am indebted to Profs. Stowell and Spalding. 



University of Michigan. 



Physical Laboratory, June 10, 1SS2. 



THE DIFFERENTIAL STAINING OF NUCLEATED 

 BLOOD CORPUSCLES. 



BV ALLEN Y. MOORE, M. D. 



IT has been urged against the differential staining of histological 

 structures, that the process may induce an alteration which may 

 be mistaken for the normal condition. That this is, in many cases, 

 true, is beyond question, but the exceptions are far too numerous 

 to justify it as a rule. 



For some years past I have used a process for the double 

 staining of nucleated blood corpuscles, which causes no alteration, 

 except of course in color, and as the structure can be seen much 

 better in a semi-transparent than in a more perfectly trans- 

 parent body, the corpuscles thus stained, offer advantages for study 

 which are not found in those left unstained. 



The fluids used for this purpose, are two, which I shall desig- 

 nate as A and B. Their formulas are as follows: 



A. 

 Eosin, 5 grains. 

 Distilled water, 4 drachms. 

 Alcohol, 4 drachms. 

 Dissolve the eosin in the water and add the alcohol. 



B. 

 Methyl analin green, 5 grains. 

 Distilled water, i ounce. 

 The blood should be spread upon the slide, by placing a drop 

 upon one end and quickly drawing the smooth edge of another 

 slide over it. This, if well done will leave a single layer of cor- 

 puscles evenly spread over the central part of the slide. 



When the corpuscles on the slide are thoroughly dry, which 



