24 
BULLETIN 555, U. S. DEPARTMENT OF AGRICULTURE. 
Mel hod of test- 
ing. 
General. 
Physical and 
chemical proper- 
ties. 
Methods of 
testing. 
5. Loss at 163° C. (325° P.), 5 hours, not more than 
per cent. 
(a) Penetration of residue at 25°C. (77°F.), 100 g., 5 
sec, not less than 
6. Total bitumen (soluble in carbon disulphide) not less 
than per cent. 
(a) Organic matter insoluble, not more than * 
per cent. 
(&) Inorganic matter insoluble, not more than 
per cent. 
(or to per cent). 
Tests of the physical and chemical properties of the asphalt 
cement shall be made in accordance with the methods described, 
or referred to on page of these specifications, tests 
Nos. 
Notes. — (1) In some instances it may be considered desirable 
to include an 86° B. naphtha solubility clause, in which case the 
wording should be : Per cent of total bitumen insoluble in 86° B. 
naphtha, to per cent. ^ 
(2) In some instances it may be considered desirable to in- 
clude a fixed carbon requirement, in which case the wording 
should be : Fixed carbon, to per cent. 
(3) In certain cases the inclusion of all the tests listed or noted 
may not be desirable, but it is necessary to use certain combina- 
tions of the tests in order to secure a material suitable for a 
specified purpose. 
SPECIFICATION FOR TARS FOR COLD APPLICATION. 
The tar shall be homogeneous. 
It shall meet the following requirements : 
1. Specific gravity 25°/25° C. (T7°/T7° F.), to 
2. Specific viscosity at ° O.* ( ° P.), to 
3. Total distillate by weight : 
Per cent. 
To 170° C. (338° F.), not more than 
To 235° C. (455° F.), not more than 
To 270° C. (518° F.), not more than | 
To 300° C. (572° P.), not more than 
(a) Melting point of residue ° C. ( ° P.), 
to ° C°. ( ° P.). 
4. Total bitumen (soluble in carbon disulphide. to 
per cent. 
Tests of the physical and chemical properties of the tar shall 
be made in accordance with the methods described, or referred 
to, on page of these specifications, tests Nos. 
Notes. — (1) In some instances it may be desirable to insert a 
specific gravity of distillate requirement after the melting point 
requirement, in which case the wording should be: (b) Specific 
gravity of total distillate 25°/25° C. (77°/77° P.), to 
(2) In some instances it may be considered desirable to insert 
a requirement for solubility in dimethyl sulphate of one or more 
fractions of the distillate. In such cases insert as follows: 
Solubilitv in dimethyl sulphate of distillate from ° C. 
( ° F.) to ° C. ( ° F.). to per 
cent. 
* It is recommended that the viscosity determination be made at 
25° C. (77° F.) or 40° C. (104° F.), according to the nature of the 
product rlosirpd. 
