SAMPLING AXIt TESTING HIGHWAY MATERIALS. 43 
in a cylinder graduated to tenths of a cubic centimeter. The dis- 
tillate will consist of xylol and water. The water will separate 
and ollect in the bottom of the cylinder where the amount may 
be read off and calculated in percentage. 
5. Oil— Take a C. S. & S. capsule or a folded hard paper (C. S. Oil. 
& S. No. 575 i which has been previously extracted with benzol 
and dried. Weigh into this about 5 to 10 grains of borings, 
making the weighing in a weighing bottle. The capsule and bor- 
ings are then extracted in some suitable extraction apparatus 
using benzol as the solvent until the washings run through prac- 
tically colorless. Chloroform is then substituted for benzol as the 
solvent until the washings again run through practically colorless. 
The extraction removes from the borings water, rosin, and oil. 
6. Rosin. — The benzol and chloroform washings are united and Rosin. 
shaken out in a separatory funnel with a 3 per cent solution of 
sodium carbonate or preferably sodium hydrate, using about three 
100 cubic centimeter portions. The alkali washings are drawn off 
and united, acidulated with sulphuric acid, and then shaken out 
with petroleum ether. The ether washings are united and filtered 
into a tared flask, evaporated on a hot plate, and the residue dried 
in the oven. This residue represents mainly rosiu, although there 
is a possibility that it may contain some tar acids from the oil. 
The amount of oil with which the block is impregnated is obtained 
by taking the percentage of extract as determined under '-Oil"' 
and subtracting from it the percentage of water plus rosin. 
7. All these results shall be expressed in percentage of the origi- 
nal weight of the block, and also in pounds per cubic foot. 
METHODS OF SAMPLING AND TESTING BITUMINOUS 
MATERIALS. 
(A. S. T. M. tentative method, serial designation, D 140-22 T, slightly 
modified.) 
1. Samples may be taken for either of two purposes : 
(a) To represent as nearly as possible an average of the bulk of 
the material sampled. 
(b) To ascertain the maximum variation in characteristics 
which the material may possess. In either case they shall be 
obtained by methods hereinafter described. 
2. (a) Care shall be taken that the samples are not contami- 
nated with dirt or any other extraneous matter and that the 
sample containers are perfectly clean and dry before filling. 
(b) Immediately after filling, the sample containers shall be 
tightly closed and properly marked for identification on the 
container itself or on a linen tag attached to the container. 
3. (a) Whenever practicable, bituminous material shall be 
sampled at the point of manufacture, and ;it such time as to allow 
the tests controlling acceptance or rejection to be made in ad- 
vance of shipment. 
(b) When impracticable to take samples at the point of manu- 
facture, they should be taken from the shipment immediately upon 
delivery. 
4. For routine laboratory examination to determine the accepta- 
bility of a given lot. not less than 1 quart of material should be 
submitted which should bo representative of the average sample 
collected as hereinafter described. 
5. Containers for liquid bituminous materials shall be small- Containers. 
mouth cans with cork-lined screw caps. Containers for semisolid 
and solid materials shall be friction top cans. 
I. SAMPLING AT PLACE OF MANUFACTURE. 
G. The inlet and outlet to the storage tank shall be sealed and 
a 1-gallon sample drawn from the top. middle, and bottom con- 
tents. The sample may be taken from drain cocks on the side of 
the tank, if such are available. Enough material should be dis- 
