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CHAPTER Y 

 REAGENTS 



Little attention is given in the present work to micro-chemical 

 reactions for the reason that their value has been much over- 

 rated in the past. A few reagents will be found useful, however, 

 and these few are given, as well as their special use. They are 

 as follows : 



LIST OF REAGENTS 



Distilled Water. Is used in the alcohol, glycerine, and water 

 mixture as a general mounting medium. It is used when warm 

 as a test for inuhn and it is used in preparing various reagents. 



Glycerine. Is used in preparing the alcohol, glycerine, and 

 water mixture, in testing for aleurone grains, and as a temporary 

 mounting medium. 



Alcohol. Is used in preparing the alcohol , glycerine, and water 

 mixture, in testing for volatile oils. 



Acetic Acid. Both dilute and strong solutions are used in 

 testing for aleurone grains, cystoliths, and crystals of calcium 

 oxalate. 



Hydrochloric Acid. Is used in connection with phloroglucin 

 as a test for lignin and as a test for calcium oxalate. 



Ferric Chloride Solution. Is used as a test for tannin. 



Sulphuric Acid. Is used as a test for calcium oxalate. 



Tincture Alkana. Is used when freshly prepared by 

 macerating the granulated root with alcohol and filtering, as a 

 test for resin. 



Sodium Hydroxide. A five per cent solution is used as a 

 test for suberin and as a clearing agent. 



Copper Ammonia. Is used as a test for cellulose. 



Ammonical Solution of Potash. Is used as a test for fixed 

 oils. The solution is a mixture of equal parts of a saturated 

 solution of potassium hydroxide and stronger ammonia. 



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