Chemastry and Physics. 229 
the reaction. proceeding quietly. On fractioning the hydrocar- 
bons obtained two products were collected, one boiling from 270° 
to 290°, and the other above 350°. The was an oil, color- 
less, highly refractive, of an agreeable odor, having the formula 
C,,H,,, or that of stilbene or diphenyl-ethylene. Its boiling point, 
and its state as a liquid show it to be the dissymetrical stilbene 
of Hepp. To prove this dissymetry still further, it was oxidized 
with chromic acid, saturated with sodium carbonate, and the 
crystallized sodium salt distilled. The substance obtained boiled 
at 295°-300°, crystallized on cooling in large white rhombic 
prisms, fusing about 48°, and was therefore pure benzophenone, 
ical examination. He gives the Neue Freie Presse of Vienna 
credit for the statement in 1871 that 300 persons had gone from 
‘ew York to Lower California to collect these lichens then lately 
discovered. They were found on hard, rocky soils near the coast, 
and a single person could collect a ton, valued at 300 dollars, in 
four days. Inthe year 1870 the archil sold in the United States 
from this source was valued at $14,900, and the extract prepared 
from it at $4,700. The lichens found their way to the London 
down by carbon dioxide gas, and the chromogen was purifie 
