16 BULLETIN 407, U. S. DEPARTMENT OF AGRICULTURE. 
No. 2 of the mixing plant at station 95 + 00, and some bituminous 
material was lost in the long haul. The analysis of the fluxed native 
asphalt is shown in Table 8. 
Experiment No. 17. — Bituminous Macadam (Penetration Method). Granite 
with Fluxed Native Asphalt A. 
Location: Station 192+00 to station 200+00. 
Total length: 800 feet. 
Total area: 1,422.2 square yards. 
The base of this section consisted primarily of an old water-bound 
trap macadam road, which was scarified and reshaped. It was 
necessary to widen the old road an average of 2 feet. The added 
width of base was of "l-£-inch" granite, which was also used to 
supplement a few weak spots in the old macadam base. The entire 
base was thoroughly rolled and compacted by a 10-ton roller. No 
binder was used. 
The method of laying the surface in this experiment was exactly 
similar to that of experiment No. 13. The materials used, however, 
were fluxed native asphalt A and " 1^-inch" granite. The properties 
of the asphalt are shown in Table 8, and the physical properties and 
mechanical analysis of the granite are shown in Tables 4 and 5, 
respectivelv. The mechanical analvsis of the chips used is shown in 
Table 7. 
Experiment No. 18. — Bituminous Macadam (Penetration Method). Granite 
with Oil- Asphalt X. 
Location: Station 200+00 to station 208+89. 
Total length: 889 feet. 
Total area: 1,580.4 square yards. 
The base of this experiment from stations 200 + 00 to 201+00 was 
similar to that described for experiment No. 17. From stations 
201+00 to 208 + 89 the old macadam was entirely removed to revise 
the grade, and a base of "l§-inch" granite was laid to a loose depth 
of 6 inches and thoroughly compacted by a 10-ton macadam roller 
without the addition of any binder. 
In other particulars this experiment was exactly similar to experi- 
ment No. 17, except that an oil-asphalt X was used with properties 
as shown in Table 8, instead of fluxed native asphalt. 
Experiment No. 19. — Bituminous Macadam (Mixing Method). Granite 
with Oil-Asphalt X. 
Location: Station 215+28 to station 225+10. 
Total length: 982 feet. 
Total area: 1,728 square yards. 
The base of this experiment was an old water-bound trap-rock mac- 
adam road, rather badly out of shape. It was scarified and reshaped 
from station 219 + 00 to the end of the experiment. From stations 
