Physics and Chemistry. 407 
iodine upon ferrid-cyanid of potassium and Stideler promises a 
further investigation of the subject—Ann. der Chemie u. Phar- 
macie, |xxv, 1. . Ge 
11. Researches on Vanadium—Roscor has continued his fine 
investigation of the compounds of vanadium and in the second 
chlorine; its density at 0° C. is 1:8584; it does not solidify a 
~ 18° C., is decomposed on boiling and even at ordinary temperatures 
into trichlorid and free chlorine. Water decomposes the tetra- 
chlorid into chlorhydric acid and a blue solution of the tetroxyd 
The tetrachlorid does not combine with bromine, Vana- 
i=) 
gg 
@ 
-P 
or” 
& 
ch 
ur 
™M 
oF 
— 
i=) 
m 
ia) 
mn 
i) 
3S 
i) 
ot 
° 
i=} 
a 
fe] 
ad 
_ 
° 
a 
i] 
Ro) 
: 
= 
S 
Nie} 
nal 
So 
oO 
f=¥) 
— 
—_ 
i) 
is] 
oe 
and afterward, at a higher temperature, loses all its chlorine, leay- 
ing the metal as a gray lustrous powder. It is very hygroscopic 
chlorine forming the tetrachlorid; heated in a current of nitro- 
gen the mono-nitrid is formed.— Chemical News, vol. xx, 37, 38. 
. Ge 
On a new apparatus for the measure of the thermic expan- 
sion of solids.—Prof. J. Miitter has made an application of Pog- 
gendorff’s mirror-arrangement to the measurement of the expansion 
of solids. The apparatus used for the purpose is described in full 
and the details of a measurement in the case of an iron bar are 
Slven.— Pogg. Ann., exxxv, 672. W. G. 
Ne ode. : not a little remarkable that neither Prof. Miller 
hor the distinguished editor of the Annalen s be aware of 
the fact that the above mentioned instrument is not new either . 
principle or in application. The reflecting pyrometer was invente 
mm 1826 by Mr. econ now of Washington, D. C.,and used by him 
. 
