CHEMICAL MICROSCOPY 



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Fig. 2b. Ethylamine HCl with 1.3 HAuBr4 in 

 9H3P04-2H20 15HBr, (24), 135X. 







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Fig. 2c. Ethylamine HCl with 1.8 HoPtle in 

 diluted H2SO4 , (100). lOOX. 



methylenetetramine), (CH2)6N4 . The low 

 organic amines cannot give such a highly- 

 condensed product, and under the conditions 

 specified here will hardly give more than 

 trace reactions nevertheless they will inter- 



FiG. 2d. Dimethylamine HCl with iodine-KI 

 reagent B-1. Yellow-brown diamonds and hexa- 

 gons, fairly large at periphery of crystallization. 

 Similar crystals are given by methylethylamine 

 HCl, but only dimethylamine gives red hexagons 

 forming among and from the little crystals (2e) . 



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Fig. 2e. Dimethylamine HCl with iodine-KI 

 (5:80) in H3PO4 (2:1) (iodine-KI reagent B-1). 

 (direct addition) lOOX. Crystal red plates, form- 

 ing from and among little brownish yellow plates 

 or flakes. 



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