118 Scientific Intelligence. 
that we have crystallographically Nb,0,=WO,. A reduction of the 
equivalent of iungsten so as to make tungstic acid W,0, does not 
appear to be admissable——Pogg. Ann., exviii, 406. W. G 
G 
ote.—Since niobic acid, NbO,, unquestionably belongs to the same 
argument for writing the chlorids NbCl, and TnCl,. On the other 
and Marignac has recently shown that the oxy-fluo-tungstates are 
isomorphous with the fluo-titanates, since we have TiF, CuF=WO,C 
+WF,Cu. Marignae writes this equality Ti, F,Cu,=W,0,F,Cu, 
WO,F,Cu, and assumes that @,—=F,. This obliges us 
to admit that in this compound Ti, =W,, while the view, which we have 
taken above requires Nb,=Ti,=W, since Nb=Ti in combination 
i —s produced by tungsten upon the qualities of bronze, cast iron 
stee 
metals. The crude tungsten contains iron, manganese. and carbon and 18 
now sold at 375 the kilogramme, a price which will probably be still 
farther reduced. Tungsten as thus prepared was found inéapable of form- 
with a brilliant lustre so that tungsten steel is easily recognized by® 
eye. Poor steel requires more tungsten than stcel of good 
quality. A good cement steel alloyed with 5 per 100 of tungsten gave 
a steel of excessive hardness which, however, forged very well, though it 
Tequired rdinary steel. 
ired much more force than o After tempering, it 4 
ing true alloys with copper, tin, and gun-metal, the latter becoming lS 
harden 
