12 BULLKTIX 1216, U. S. DEPABTMBNT OF AGRICULTURE. 
.". (a) The percentages in sieve analysis shall he reported to 
the nearest whole number. 
(b) If more than 15 per cent of a fine aggregate Is coarser 
than i he No. 4 sieve, or more than 1;" per cent of a coarse aggre- 
gate is liner than the No. 4 sieve, the sieve analysis of the por- 
tions finer and coarser than this sieve shall he reported sepa- 
rately. 
Notb. — It is recommended that the one-quarter-inch sieve be used 
rather than the No. 4 sieve and such additional U. S. Bureau of 
Standard sieves as may be decided as test limits. The Tyler standard 
screens 100. 48, 28, 14. s, 4 and three-eighth-lnch come within the 
tolerance allowed for the Bureau of Standard screens 100. 5<>, 'MK 
16, 8, 4 and three-eighth-inch. 
TEST FOR APPARENT SPECIFIC GRAVITY OF SAND, 
STONE, AND SLAG SCREENINGS, AND OTHER FINE 
NONBITUMINOUS HIGHWAY MATERIALS. 
(A. S. T. M. standard method, serial designation D 55-10, slightly 
modified.) 
1. The following tests. " Le Chatelier " and "Jackson," are 
equally suited for use in determining the apparent specific gravity 
of sand, stone, and slag screenings and other fine nonbituminous 
highway materials, and may he considered as alternates. 
LE CHATELIER TEST. 
Le Chatelier 2. The determination of specific gravity shall be made with a 
test. standardized Le Chatelier apparatus. This apparatus is stand- 
ardized by the Tinted States Bureau of Standards. Kerosene, 
free from water, or benzene, not lighter than 62° Baume\ shall 
be used in making this determination. 
3. (a) The flask shall be filled with either of these liquids to 
a point on the stem between zero and 1 cubic centimeter and 
64 grams of sand or other fine nonbituminous highway material 
of the same temperature as the liquid shall be slowly introduced, 
taking care that the material does not adhere to the inside of 
the flask above tlie liquid and to free the material from air by 
rolling the flask in an inclined position. After all material is 
introduced the level of the liquid will rise to some division of 
the graduated neck : the difference between readings is the volume 
displaced by 04 grams of the material. The specific gravity shall 
then be calculated from the formula: 
Weight of material (grams.) 
y~ Displaced volume (centimeters.) 
(&) The flask, during the operation, shall be kept immersed 
in water, in order to avoid variations in the temperature of the 
liquid in the flask, and any variation that occurs shall not exceed 
0.5° C. The results of repeated tests should agree within 0.01. 
JACKSON TEST. 
J k test 4- Tn0 determination shall be made with a Jackson specific- 
ac $0 ' gravity apparatus which shall consist of a burette, with gradua- 
tions reading to 0.01 in specific gravity, about 23 centimeters 
(it inches i long and with an inside diameter of about 0.0 centi- 
meter (0.25 Inch), which shall be connected with a glass bulb 
approximately 13 centimeters (5.1 inches) long and 4.5 centi- 
meters (1.75 inches) in diameter, the glass bulb being of such 
size that from a mark on the neck at the top to a mark on the 
burette just below the bulb, the capacity is exactly 180 centi- 
meters (6.09 liquid ounces); and an Erlenmeyer flask, which 
shall contain a hollow ground-glass stopper having a neck of the 
same bore as the burette and a capacity of exactly 200 centi- 
meters (6.70 ounces) up to the graduation on the neck of the 
stopper. 
