138 PROCEEDINGS OP THE AMERICAN ACADEMY 



3. The highest number of atoms of base observed in any case is 

 six (old style), which implies that each acid contains twelve atoms of 

 hydroxyl. 



4. In all cases observed the number of atoms of hydroxyl replaced 

 by a monatomic metal is even. 



5. One instance occurs in which two acid phospho-tungstates of 

 different orders appear to unite to form a definite compound ; but this 

 case admits of a different explanation. 



6. In all phospho-tungstates studied the number of atoms of base 

 or of hydroxyl is more than sufficient to saturate the phosphoric oxide 

 present, if we admit that the acid is 1 2-basic. At least a part of the 

 hydroxyl or base must therefore be united to tungstic oxide. 



For greater facility of comparison I have brought together the 

 formulas of all the compounds described in this paper, writing them 

 both with the old and the new notation. 



24 W0 3 . P 2 6 . 6 H 2 + 47 aq W 24 P 2 71 ( HO ) 12 + 47 aq 



24 W0 3 . P 2 5 . 6 H 2 + 34 aq W 24 P 2 O n (HO) 12 + 34 aq 



24 W0 8 . P 2 6 . 6 H 2 + 55 aq W 24 P 2 7l (HO) 12 + 55 aq 



24 W0 8 . P 2 5 . 2 Na 2 . 4 H 2 +23 aq W 24 P 2 71 (NaO) 4 (HO) 8 + 23 aq 



24 W0 8 . P 2 6 . 3 K 2 . 3 H 2 + 8 aq W 24 P 2 7l (KO) 6 (HO) 6 + 8 aq 



24 W0 3 . P 2 6 . 3 K 2 . 3 H 2 + 14 aq W 24 P 2 71 (KO) 6 (HO) 6 + 14 aq 



24 W0 8 . P 2 5 . 3(NH 4 ) 2 0.3H 2 + 26aq W 24 P. 2 7l (NH 4 0) 6 (HO) 6 + 2G aq 



24 W0 3 . P 2 5 . 3 BaO . 3 H 2 + 43 aq W 24 P. 2 71 (Ba0 2 ) 3 (HO) 6 + 43 aq 



22 W0 3 . P 2 5 . 2 K 2 . 4 H 2 + 2 aq W 22 P 2 65 (KO) 4 (HO) 8 + 2 aq 



22 W0 3 .P 2 5 .3(NH 4 ) 2 0.3H 2 + 18aq W 22 P 2 65 (NH 4 0) 6 (HO) 6 + 18 aq 



22 W0 3 . P 2 5 . 2 Na 2 . 4 H 2 + 5 aq W 22 P 2 65 (NaO) 4 (HO) 8 + 5 aq 



22 W0 8 . P 2 5 • 4 BaO . 2 H 2 + 39 aq W 22 P 2 65 (Ba0 2 ) 4 (HO) 4 + 39 aq 



20 W0 3 . P 2 3 . 6 BaO + 48 aq W 20 P 2 O 69 (BaO 2 ) 6 + 48 aq 



18 W0 3 . P 2 6 . 6 K 2 + 23 aq W 16 P 2 53 (KO) 12 + 23 aq 



18 W0 3 . P 2 5 . 6 K.,0 + 30 aq W 18 P 2 53 (KO) 12 + 30 aq 



18 W0 8 . P 2 5 . K 2 . 5 H 2 + 14 aq W 18 P 2 53 (KO) 2 ( HO) 10 + 14 aq 



16 W0 3 . P 2 5 . CaO . 5 H 2 + 3 aq W 16 P 2 O 47 (CaO 2 )(HO) 10 + 3 aq 



16 W0 3 . P 2 5 . 4 K 2 . 2 H 2 + 19 aq Wi 6 P 2 47 (KO) 8 (HO) 4 + 19 aq 

 16 W0 8 . P 2 5 . 6 (NH 4 ),0 + 10 aq W 16 P 2 47 (NH 4 0) 12 + 10 aq 



14 W0 3 . 2 P 2 6 . 5 Na 2 + 42 aq 



6 W0 3 . As 2 O s .31,0.3 H 2 W 6 As 2 27 (KO) 6 (HO) 6 



6 W0 3 .As 2 6 .4(NH 4 ) 2 0.2H 2 + 3aq W 6 As 2 27 (NH 4 0) 8 (HO) 4 + 3 aq I 



1G W0 3 . As 2 5 . 6 Ag 2 + 11 aq W 16 As 2 47 (AgO) 12 + 11 aq 



