106 Proceedings of Learned Societies. 
little; then fusel oil, wood-spirit, and oxalic ether, which are also nearly 
alike ; acetic acid, oil of turpentine, glycol, carbolic acid, liquid eps 
boiling at 360° F., and bisulphid of carbon. Finally, tereblorid and oxy- 
chlorid of phosphorus, although saifeatly colorless and limpid, arrest all 
the chemical ra 
The experiments upon aeriform bodies yielded important results ; they : 
mah but little coincidence with those of Tyndall on the absorptive power — 
the gases for radiant heat. These experiments were made by interpo- — 
ee in the track of the ray between the vertical slit and the quartz prism, : 
a brass tube two feet pee closed at each end air-tight by means of a — 
plate of quartz. Each or vapor in succession was introduced into the — 
tube, and the results Siaapaeed with those ae by causing the rays — 
to traverse the tube when filled with atmospheric 
mongst the colorless pases, oxygen, hydrogen, nitrogen, oT : 
This absorbent action of these 
compounds of sulphur and phosphorus is very striking. 
appears to owe its remarkable power of arresting the 
— 
a column of atmospheric air two feet long, exerts a still more power? 
absorbent effect than coal-gas. 
n the other hand, the effect of a similar arrangement, in which 
pupae of ether, of chloroform, and of oil of turpentine was onlay 
for that of benzol, gave effects which, though perceptible, were muc 
marked. An arbitrary scale is laid down, by which a comparative es 
mate of the absorptive power of each compound, whether solid, 
tuted a series of ex periments, in which a part metallic specul 
stituted for the lens of rock-crys stal; but the loss of chemical pore 
the reflected rays was so considerable, _ this loss occurred so un 
at different points, that the method was abandoned. The reenlt of the 
RIE a action — light palleched! at an angle of 45° from the pol 
ished surface of several of the principal metals is given. The reflection 
from god, although He very intense, was found to be more uniform 
an that from any other metal that was tried. Burnished leat 
io 
deficient in some portions of the less refrangible rays, althou; fe in me 
ar ae the Fedention:s is = perfect, — for rays 
