valens), but frequently exert only bivalent, trivalent, 

 or quadrivalent activity. 



Roman numerals i, n, in, iv, v, vi, are attached to 

 the symbols of each element to indicate atomic 

 univalence, bivalence, trivalence, quadrivalence, 

 quinquivalence, or sexivalence. Dashes (H', O", 

 N" ')similar to those used in accentuating words are 

 often used instead of figures in expressing quantiva- 

 lence. The quantivalence of elements, as they one 

 after another come under notice, should be care- 

 fully committed to memory; for the composition of 

 compounds can often be thereby predicted with 

 accuracy and remembered with ease. 



TABLE OF ELEMENTARY SUB- 

 STANCES. 



Symbols and atomic 

 value. 



Aluminium (A1 2 VI ) Al 1 



Antimony (Sb m ) Sb v 



Arsenicum (As 111 ) As v 



Barium Ba 11 



Beryllium ( Glucinum )..'......... Be 11 



Bismuth (Bi ni ) Bi v 



Boron B in 



Bromine Br 1 



Cadmium Cd 111 



Caesium Cs 1 



Calcium Ca 11 



Carbon (C 11 ) C IV 



Cerium (Ce in ) Ce VI 



Chlorine Cl 1 



Chromium (Cr 2 VI ) Cr VI 



Cobalt (Co 11 ) Co VI 



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