Chemistry and Physics. 459 
The preceding table contains the wave-lengths for the most 
intense lines, bands or groups of lines which characterize the 
spectra of several metallic vapors. e numbers are expressed 
in millionths of a millimeter, and are generally exact to one or 
two millionths of a millimeter. 
ve several rather feeble bands or groups of lines; 
while iron, in our experiments, gave no band sufficiently intense 
to exam 
The sentia, meer above, show how rich the field of research 
is which the phenomena of phosphorescence open up in the invisi- 
ble part of the ukaaed of the spectrum which, alone, covers 
an interval of wave-lengths greater sina a visible and ultra- 
violet parts together 
esides the interest it may excite by proving the er of 
these rays, of which the wave-lengths are considerable, in the 
spectra of metallic vapors, this research, more than any other, is 
and eg in the Infra-red portion of the Solar Spectru 
Note ENRI BecquEeReL.—In a recent communication to 
the ‘Académi ie des Sciences* on the lines in the infra-red part of 
ed 
make in the numbers adopted in a a researcht for the 
es iy aac of —— lines ae bands in the solar spectrum. 
now give a ré of m , determinations of the wave- 
to a similar saaals yom the two others. In m for mer researches 
I i ndinates these bands, starting from A, by the letters A’, A’, 
and Al’, 
the wave-lengths of these rays do not allow of the Seige gr 
with any certainty, of the results of their researches. In 1847 
* Comtes Rendus, August 25, 1884; Phil. Mag., eee 386. 
+ Annales de Chimie et de Physi ique, 5° série, t, xxx, p. 5 
