144 PRELIMINARY REPORT ON COAL-TESTING PLANT, [bull.261. 
tar an apparent reaction took place, which caused the separation of 
some of the intrained water. This asphalt was tried alone with 
Arkansas coal, 4 per cent of asphalt being used, and even when heated 
dry at a high temperature the resulting' briquette was poorly coherent. 
With 6 per cent of asphalt the briquette was little or no better, indi- 
cating that the asphalt alone has no binding properties, as was sup- 
posed from the very small amount of volatile matter that it contained. 
Wyoming asphalt, i?£.— This asphalt united readily with rosin, and 
in preparing a mixture for briquetting 2 parts of asphalt and 1 part 
of rosin were melted in a kettle and cooled over night. On a cool, 
frosty day this mass was very brittle, but became sticky with a rise ini 
temperature. In using the mixture 1 to 2 parts of lime were added 
to prevent its becoming too soft while hot. The briquettes made from 
this mixture were all right in appearance, but in burning they crum- 
bled easily, not standing up well in the fire. 
In testing this asphalt alone it was necessary to heat the coal in an 
assay crucible, adding the fragments of asphalt and kneading them 
together with repeated heatings. Six per cent of this asphalt alone 
would make a strong, tough briquette with Wyoming lignite, which] 
was slightly earthy in appearance. When tested in the fire, howeverj 
the briquette fell to pieces at once and completely. 
ROSIN. 
uettesl 
brittll 
In using rosin alone it was found to make hard, brittle briqi 
but they were not satisfactory, principally on account of their 
ness, which would prevent their standing rough treatment in trans- 
portation. The results of the tests made with rosin and pitch have 
been recorded under "Pitch." Rosin mixes with almost all the crude 
oils and their residual products which have been tested in the labora- 1 
tory. With the rubbery asphalt, B2, it mixes readily, forming a still 
more rubbery mass. With the Indian Territory, B4, it does not unit* 
at all. All of the oils and petroleums increased the toughness of thi 
rosin, and the resulting masses varied from the consistency of wagor 
grease to sticky rosin. Five parts of rosin melted with 1 part o> 
Kansas crude petroleum gave a tough mass that could just be cracker 
when cold, and this seemed to be the best ratio for these two cor 
pounds. With lime alone it was found that 15 per cent of lime and 8 
per cent of rosin were required for a complete reaction. Rosin wit 
unslacked lime sets after melting. If the slacked lime is used thi 
action occurs at 212° F. and the mass is light gray. This cemer: 
softens and becomes sticky only at the melting point of lead. On coo 
ing it is brittle, but stronger than rosin. With slacked lime rosi 
reacts and gives a satisfactory mixture up to 3 parts of rosin and 
part of slacked lime. A combination of rosin and the residual Beai 
mont petroleum, P2, was made considerably tougher by the additic 
