DUST PREVENTION AND ROAD PRESERVATION. 
21 
Experiment No. 4. — Residual asphaltic petroleum — Hot application. 
Location: From station 209+00 to station 280+00. 
Length: 7,100 feet. 
Date of application: From October 9 to October 15. 
Temperature of oil: Maximum 210° F., minimum 165° F., average 188° F. 
Table 24. — Analysis of residual asphaltic petroleum 1 used in experiment No. 4- 
Specific gravity 25 /25° C 1. 002 
Flash point ° C 86 
Burning point ° C 175 
Viscosity, Engler, 100° C, 50 c. c. specific 21. 
Per cent of loss at 163 ° C, 5 hours (20 grams) 9. 23 
Float test of residue (50° C.) (time) 2 2'42" 
Per cent of bitumen insoluble in 86° B. naphtha 10. 55 
Per cent of fixed carbon 5. 63 
Per cent soluble in CS 2 (total bitumen) 99.93 
Per cent of organic matter insoluble .06 
Per cent of inorganic matter insoluble 01 
Total 100.00 
Details. — From station 241+50 to station 251+07 the macadam was 
first well sprinkled with water and the oil was applied while the road 
surface was still moist. Owing to the viscosity of the oil and the 
cool weather, some difficulty was experienced in starting the dis- 
tributor pump. This resulted in the formation of pools of thick oil 
at the beginning of each trip before the nozzles worked uniformly 
enough to have the team start. After a few experiences with this 
trouble, the distributor nozzles were allowed to discharge into the 
ditch until a uniform distribution began. 
Experiment No. 5. — Residual asphaltic petroleum — Hot application. 
Location: From station 280+00 to station 347+75. 
Length: 6,775 feet. 
Date of application: From October 21 to November 21. 
Temperature of oil: Maximum 221° F., minimum 167° F., average 200° F. 
Table 25.- — Analysis of residual asphaltic petroleum : used in experiment No. 5. 
Car No. 1 
Car No. 2. 
Specific gravity 25 °/25 ° C 
V iscosity, Engler, 100° C, 50 c. c. specific 
Float test at 50° C. (time) 
Per cent of loss at 163 ° C, 5 hours (20 grams) 
Float test of residue (50° C.) (time) 3 
Per cent of total bitumen insoluble in 8(5° B. naphtha 
Per cent of fixed carbon 
Per cent soluble in CS 2 (total bitumen) 
Per cent of organic matter insoluble 
Per cent of inorganic matter insoluble 
Total 
0.990 
26.0 
1'28" 
3.03 
2'50" 
19.29 
10.47 
99.97 
.02 
.01 
100. 00 
0.998 
37.5 
1'26" 
2.63 
2'45" 
18. 83 
10.64 
99.90 
.10 
.00 
i Sticky, viscous fluid. 
Sticky, semisolid. 
3 Soft, sticky. 
