BULLETIN 407, U. S. DEPAETMENT OF AGRICULTURE, 



Table 7. — Mechanical analyses of stone chips. 



Sandstone. 



Gneiss. 



Trap. 



Granite. 



Passing li-inch, retained on 1-inch screen . 

 Passing 1-incli, retained on |-inch screen . . 



f-inch, retained on J-inch screen . . 



J-incb, retained on J-incli screen . . 

 _ ^inch, retained on T'o-incli screen . 

 Passing ^Viiicn screen 



Per cent. 



Per cent. 



Per cent. 



2.0 

 25.1 

 66.0 



6.7 



0.5 



6.1 



27.3 



61.5 



4.6 



15.8 

 25.8 

 32.9 

 19.4 

 6.1 



Per cent. 

 1.1 



3.8 

 35.7 

 47.1 



\ 112.3 



99.8 



100.0 



100.0 



100.0 



1 Passing ^incli screen. 

 Table 8. — Analyses of fluxed native asphalts and oil-asphalts. 



Fluxed native 



Specifi- 

 cation A. 



Experi- 

 ment 

 numbers 

 1, 3, 5, 8, 

 14, 1^, 

 17, 20. 



Specifi- 

 cation B. 



Oil asphalts. 



Specifi- 

 cation X. 



Experi- 

 ment 

 number 

 10. 



Experi- 

 ment 

 numbers 

 2, 4, 6, 7, 

 13,16, 

 18, 19. 



Specifi- 

 cation Y. 



Experi- 

 ment 



numbers 

 9,12, 



Specific gravity 25''/25° C 



Melting point °G 



Penetration at 25° C., 100 grams, 5 seconds 



Loss, 5 liours, 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 CS2 (total bitrmien) do 



Organic matter, insoluble do 



Liorganic matter, insoluble do 



1.043 



1.054 



117 



2.36 



57 



23.45 



12.48 



71 

 2.60 



34 

 24.50 

 12.66 



1.046 



50.5 



102 



0.25 



63 



26.79 



13.92 



96.65 

 1.17 

 2;18 



96.86 

 1.07 

 2.07 



99.90 

 0.07 

 0.03 



Total. 



100.00 



100. 00 



100.00 



1.049 



64 



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'j (total bitumen), per cent 87. 11 



Free carbon, per cent 12. 80 



Inorganic residue upon ignition, per cent 0. 09 



Distillation (Engler flask). 



Character. 



By vol- 

 ume. 



By weight. 



Water 



First light oUs (to 110° C) 



Second light oils (110°-170° C) . 



Heavy oils (170°-270° C.) 



Heavy oils (270°-300° C.) 



Pitch. 



Solid 



...do 



Hard, brittle.. 



Per cent. 

 0.0 

 0.0 

 Trace. 

 7.3 

 7.1 

 85.6 



100.0 



Per cent. 

 0.0 

 0.0 

 Trace. 

 5.8 

 5.7 

 88.5 



100.0 



