62 _ Editorial Correspondence. 
WO,. Pto, Nees ior ia eens PtO, . 40Am, +12 aq. 
but both belong to the yellow series. I have not yet obtained 
the 12-atom series corresponding to Marignac’s pire 
The platino-deci-tungstates ethos tungstic hydrate, W(OH),, 
on boiling, but the hydrate separates again on cooling without 
thange. Acid molybdate of sodium also dissolves  platinie hydrate 
giving a deep olive-green solution which appears red i 
ayers. The only salt of this series yet graded “crystallizes in 
amber-colored tabular plates which have the formula: 
10Mo00, . PtO, . 40Na, +29 aq. 
They are very soluble and give — pronipltates with 
many metallic solutions. I thin have also obtained the corre- 
spondi ng metameric series, but of this 3 more in dee time. The 
ohis : 
all the salts of both series effloresce strongly and the alkaline 
salts have a very distinct acid reaction, so that the limit of the 
basicity is certainly higher than eight. a am endeavoring to 
(OH),, &e. 
the formation of new complex acids I have etd definite at 
present. gets i acid appears ho seahag to be fo rmed b 
venue to ‘ por unusual exte 2 
According to my analyses, phonphotungati acid hasthe formula 
20 or Wo057P2(0OH),¢ 
independently of water of ‘rystallization. y have obeatned salts of 
this series having respectively the form : 
20W0,.P,0,.ONa.z. ny +16 aq. 
20W0,.P,0, . 2Ba0. 6OH, +18 aq. 
mS 
20W0, p 20,. 80K, +18 aq. 
