BULLETIN 407, U. S. DEPARTMENT OF AGRICULTURE. 
Table 7. — Mechanical analyses of stone chips. 
Sandstone. 
Gneiss. Trap. Granite 
Passing 1 J-incn, retained on 1-inch screen . 
Passing 1-inch, retained on f-inch screen. . 
Passing f-inch, retained on §-inch screen . . 
Passing ^-inch, retained on J-inch screen. . 
Passing J-inch, retained on T Vinch screen 
Passing T yinch screen 
Per cent. 
Per cent. 
2.0 
25.1 
66.0 
6.7 
0.5 
6.1 
27.3 
61.5 
4.6 
Per cent. 
15.8 
25.8 
32.9 
19.4 
6.1 
Percent. 
1.1 
3.8 
35.7 
47.1 
\ U2.3 
99.8 
100.0 100.0 
100.0 
i Passing £-inch screen. 
Table 8. — Analyses of fluxed native asphalts and oil-asphalts. 
Specific gravity 25725° C 
Melting point °C 
Penetration at 25° C, 100 grams, 5 seconds 
Loss, 5 hours, 163° C, 20 grams per cent. . 
Penetration of residue, as above 
Per cent of total bitumen insoluble in 86° B . naphtha 
Fixed carbon per cent . . 
Soluble in CS» (total bitumen) do 
Organic matter, insoluble do 
Inorganic matter, insoluble do 
Total. 
Fluxed native 
asphalts. 
Oil asphalts. 
Specifi- 
cation A. 
Experi- 
ment 
numbers 
1, 3, 5, 8, 
14, 15, 
17, 20. 
1.043 
117 
2.36 
57 
23.45 
12.48 
)6.65 
1.17 
2.18 
Specifi- I Specifi- 
cation B. cation X. 
I 
Experi- 
ment 
number 
10. 
1.054 
71 
2.60 
34 
24.50 
12.66 
1.07 
2.07 
100. 00 I 100. 00 
Experi- 
ment 
numbers 
2, 4, 6, 7, 
13,16, 
18, 19. 
1.046 
50.5 
102 
0.25 
63 
26.79 
13.92 
Specifi- 
cation Y. 
Experi- 
ment 
numbers 
9,12. 
99.90 
0.07 
0.03 
100.00 
1.049 
54 
74 
0.12 
49 
28.28 
18.75 
99.92 
0.05 
0.03 
100.00 
Table 9. — Analysis of refined coal tar used in bituminous gravel concrete. 
Specific gravity 25° C/25° C 1. 226 
Float test 50° C 2' 58* 
Soluble in CS-2 (total bitumen), per cent 87. 11 
Free carbon, per cent 12. 80 
Inorganic residue upon ignition, per cent 0. 09 
Distillation (Engler flask). 
Water 
First light oils (to 110° C) 
Second light oils (110°-170° C | . 
Heavy oils (l70°-270° C.) 
Heaw oils (270°-300° C. ) 
Pitch! 
Character. 
Solid 
..do 
Hard, brittle. 
By vol- 
ume. 
Per cent. 
0.0 
0.0 
Trace. 
7.3 
7.1 
85.6 
100.0 
By weight. 
Per cent. 
0.0 
0.0 
Trace. 
5.8 
5.7 
88.5 
100.0 
