254 Scientific Intelligence. 
SCIENTIFIC INTELLIGENCE. 
I, CHEMISTRY AND PHYSICS. 
1. On the chlorids af tungsten.—Dersray has studied the vapor-den- 
sities of the volatile compounds of tungsten with chlorine, and with chlo- 
rine and oxygen, and has arrived at results of much theoretical interest. 
en a current of age! chlorine is passed over metallic tungsten heated 
to redness in a tube of hard glass, red vapors are obtained which con- 
dense to a dark gray mass, which is a mixture of the two chlorids WC, 
and W,Cl,. By distillation in a current of chlorine the terchlorid 
WCl,, may be obtained very nearly pure. There are, as is well known, 
oxalic acid. th e red ox “ie rid or, as_we should as to term it, ae 
vow O Cl,+WO,. 
The terchlorid heated with tungstic acid acts upon it with evolution of 
heat, according to the equation, 
WO,+2WC!,=—3WOCI,. 
The easy decomposition of the dioxychlorid makes it sy ealnes to deter- 
mine vi ay of its vapor, but the vapor-densities of the two other 
on eg Laan of 2 vols., ie 5°93 upon that of 4 vols. If we sins 
with that tungstic acid is wi O, and the perchlorid W’Cl,, the 
equivalent of the chlorid becomes five-thirds of the old equivalent and 
its Ss pete five-thirds of that found above theoretically, so that t if 
o 4 vols. of vapor we have for its vapor-density 
11-46, which et nearly with that found by experiment, We must 
W’'0,+2W"C 5 Which is the same as seach the existence of bodies 
the vapor-density of which corresponds to 12 volumes.— Comptes Rendus, 
: Ww. G. 
2. op ed separation of. lt from nickel—Trrreit has given & 
ting cna from nickel which promises to yield good 
veralte. o solution containing the two metals ammonia is to be 
