Chemistry and Physics. 397 
Other and more: intense flames were then tried; the results were as 
follows: 
Radiation 
Nature of the flame. Intensity of light. for unit of light per minute. 
Spermaceti candle, 1 210 
Gas flame, r2 201 
7 7:7 199 
Moderator-lamp, 8°6 199 
light due to a layer of water 20 centimeters in thickness amounted to 
of water 0-2m. in thickness was placed between the flame and the ther- 
mopile, the flame being at the same distance as in the first experiments, 
The deviation of the needle was therefore due exclusively to the heat 
produced by the rays of light. The results were as follows: 
Radiation of heat Radiation of light 
Intensity and light per minute per minute for the 
of light, for the unit of light. unit of light. 
Flame. 
Spermaceti candle, 1 4: 
Moderator-lamp, 6°25 -—— 3°9 
° 86 199 4°1 
Gas flame, 77 199 42 
* 1:2 201 
Ann.,, cxxv, 348 
ae P J. . . . 
3. Niobium and tantalum.—The continued investigations of Marie- ° 
to which we have already 
