DUST PREVENTION AND EOAD PRESERVATION, 1916. 
57 
Table 60. — Analysis of water-gas tar preparation 1 used in surface treatment of concrete 
experiment. 
Specific gravity 25°/25° C 1. 155 
Float test 32° C. (seconds), 321 ; 50° C. (seconds) 84 
Per cent free carbon 2. 22 
Per 
Distillation : 
Water 
First light oils (to 110° C.) 
Second light oils (110° to 170° C.) 
Heavy oils (170° to 270° C.) 2 14. 1 
Heavy oils (270° to 300° C.) 2 8. 9 
Pitch. 3 77. 
Per cent 
by vol- 
ume. 
0.0 
.0 
.0 
by 
weight. 
0.0 
.0 
.0 
11.7 
7.4 
80.9 
Total 100. 
Dimethyl sulphate test 
Fraction: 
270° to 300° C. 
300° to 350° C. 
350° to 375° C. 
Table 61 
Per cent 
by vol- 
ume. 
20.8 
7.0 
100.0 
Per 
cent 
insolu- 
ble. 
0.0 
5.0 
17.5 
Analysis of petroleum products used in surface treatment of concrete experiment. 
Sections C, 
D, E, and 
F, residual 
asphaltic 
petroleum. 
Sections I 
and J, as- 
phaltic pe- 
troleum. 
Specific gravity 25°/25° C 
Flash point, °C 
Burning point °C 
Specific viscosity, Engler, 50 c. c 
Float test at 50° C., seconds 
Loss at 163° C, 5 hours, 20 grams, per cent 
Float test on residue 50° C, seconds 
Per cent of total bitumen insoluble in 86° B. naphtha. 
Fixed carbon, per cent 
0.993 
U3.5 
28 
13.71 
151 
18.63 
11.25 
0.945 
37 
93 
2 97.5 
26.09 
101 
14.67 
8.5 
Bitumen soluble in CS 2 (total bitumen), per cenc. 
Organic matter insoluble, per cent 
Inorganic matter insoluble, per cent 
99. 
.03 
99.85 
.15 
.00 
Total per cent. - . 
100.00 
100. 00 
i At 100° C. 2 At 25° C- 
Sections I and J: These sections were much like C to F and had a 
rubbery mat with few breaks, but a tendency to push. With cold and 
moisture the mat became somewhat mealy under traffic. 
Experiments Nos. 4 a nd 5 — Oil cement concrete; cement concrete. — 
There was less distinction apparent this year between experiments 
Nos. 4 and 5. The gravel aggregate showed a very material wear 
in No. 5. The limestone appeared to be worn more than the gravel, 
as evidenced by conditions along the eastern 4 feet of the surface 
and especially over the last 50 feet of experiment No. 4, south of the 
Columbia Club main entrance. 
Experiment No. 6 — Vitrified orick. — There has been no great differ- 
ence in apparent wear between the several sections of this experiment. 
Very viscous. 
Clear. 
3 Hard, brittle. 
