REAGENTS AND STAINS. 205 



REAGENTS AND STAINS. 



In preparing the following regeants it is well to re- 

 member that the weight of a cubic centimeter of water 

 is one gram, and that a liter contains 1,000 cubic centi- 

 meters. The formulae that are given are those most 

 commonly used and are briefly stated : 



NORMAL, FLUIDS. 



Distilled imter.- A supply of distilled water should 

 be constantly at hand for the preparation of the re- 

 agents and stains. 



Normal saline. This is prepared by dissolving one 

 part, by weight, of sodium chloride in 150 parts of dis- 

 tilled water. 



MACERATING FLUIDS. 



Dilute alcohol. This may be prepared by mixing 

 one part of ninety-five per cent alcohol with two parts 

 of distilled water. Other fluids used for this purpose 

 are solutions of potassium bi-chromate, two per cent, 

 and caustic potash, twenty-five per cent. 



DECALCIFYING FLUIDS. 



Picric acid. Make a saturated aqueous solution of 

 picric acid. This is an excellent fluid for decalcifying 



