Abstracts 
7908] 
111 
on a hot summer’s day must have a flowing point above 120° C. 
In the winter pitch with a flowing point of 100° C. may be used. 
All softer pitches and asphalts have to be melted and mixed in 
liquid form with the coal. 
A pitch with a very high softening point, above 150° C., should 
be either thinned or superheated in the mixer. The efficient use 
of a binder depends very largely on the proper regulation of the 
conditions in the mixer. The presence of low-volatile compounds 
in the pitch to be used as a binder increases the smoke in burn- 
ing; and also increases the tendency of the briquet to soften and 
crack open in advance of combustion, owing to the volatilization 
and escape of these compounds. 
“The main problem in briquetting is to find a suitable binding 
material at sufficiently low cost. When the difference in price 
between the slack coal and the first-class lump coal is $1, the cost 
of briquetting should not exceed this amount. Of this the binder 
must cost less than 60 cents per ton, as the cost of manufacture 
averages about 40 cents. To leave out of consideration the pos- 
sible advantages in the use of briquetted coal over run-of-mine 
coal, due to the greater efficiency and smokelessness of briquets, 
it will probably not be necessary to pay any attention to binding 
materials costing $1.25 or more per ton of briquets produced.” 
The Volatile Oil of Pinus Serotina, by Chas. H. Herty 
and W. S. Dickson. Jour. Am. Chem. Soc., vol. 30, p. 872. 
May 1908. 
A study of the volatile oil obtained by distillation with steam 
from the oleo-resin of Pinus Serotina (Pond Pine) showed that it 
contained large quantities of limonene instead of the more com- 
mon pinene present in ordinary spirits of turpentine. The oil 
showed the following physical contents : 
Specific Gravity : 20° 0.8478 
Specific Rotation: 20° *— 105° 36* 
Index of Refraction : 20° 1.4734 
Acid Number: 0 
Saponification Number: 1.54 
Iodine Number: 378 
On Fractionation the oil showed: 
