22 BULLETIN 105, U. S. DEPARTMENT OP AGRICULTURE. 



Details. — Car No. 1 began to foam badly from water contamina- 

 tion after the first two loads had been applied. About 2,000 gallons 

 were used, when, owing to the difficulty of handling the material, the 

 remainder of the shipment was rejected and replaced by car No. 2. 

 From station 314 + 10 to station 320 + 70 and from station 294 to sta- 

 tion 308 the oil was applied soon after a rain while the surface of the 

 macadam was still moist. 



Experiment No. 6. — Water-gas tar preparation — Hot application. 



Location: From station 347+75 to station 411+00. 



Length: 6,325 feet. 



Date of application: November 24 and November 26. 



Temperature of tar: Maximum 248° F.; minimum 180° F.; average 214° F. 



Table 26.- — Analysis of water-gas tar preparation x used in experiment No. 6. 



Specific gravity 25°/25° C 1.15 



Float test at 32° C. (time) 2'9" 



Per cent of free carbon 1. 29 



Distillation: By volume. By weight. 



Water per cent . . 0. 0. 



First light oils to 110° C do.... 2.2 .1 



Second light oils 110°-170° C do 2. 2 .2 



Heavy oils 170°-270° C do.... 216. 7 14.9 



Heavy oils 270°-315° C. * do. . . . * 7. 5 6. 6. 



Pitch residue do 75. 4 78. 1 



Total do 100.0 99.9 



Details. — The east half of the road from station 393 + 60 to station 

 397 + 60 was treated by means of hand-pouring pots. 



Experiment No. 7. — Asphaltic petroleum — Cold application. 



Location: From station 411+00 to station 477+89. 

 Length: 6,689 feet. 



Date of application: December 4 and 5. 

 Temperature of oil: From 80° to 100° F. 



Table 27.' — Analysis of asphaltic petroleum, 5 used in experiment No. 7. 



Specific gravity 25°/25° C 0. 959 



Flash point °C 32 



Burning point ° C 41 



Viscosity, Engler, 25° O, 50 c. c. specific 114. 5 



Per cent of loss at 163° C, 5 hours (20 grams) ■ 27. 44 



Float test of residue (50° C.) i 1'53" 



Percent of total bitumen insoluble in 80° B. naphtha 7.38 



Per cent of fixed carbon 4. 28 



Per cent soluble in CS 2 (total bitumen) 99. 91 



Per cent of organic matter insoluble 08 



Per cent of inorganic matter insoluble 01 



Total. 100.00 



i Sticky, very viscous fluid. 

 ' 2 Clear. 



3 A 315°-350° C. fraction showed 5 per cent and a 350°-375° C. fraction showed 10 per cent insoluble in 

 dimethyl sulphate. 



* Clear; showed 5 per cont insoluble in dimethyl sulphate. 



s Sticky, fluid, with strong naphtha odor. 



