OFFICE OF PUBLIC EOADS. 771 



li inches in size. The third course was of stone screenings three-fourths of an inch in 

 size or smaller, and was applied in such amount as to fill the voids in the second course. 

 The fourth course, of the same size stone as that of the third, was applied in such 

 amount as was necessary to absorb what surplus oil remained on the surface. The 

 oil was furnished in a tank car of 9,000 gallons capacity and was heated by steam 

 coils to a temperature of 190° F. The road was given two applications of oil, the 

 first at the rate of 1 gallon per square yard and the second at the rate of one-half gallon 

 per square yard. The total cost of the road to the community was $3,875.05, which 

 IS at the rate of 67.06 cents per square yard, or $6,295.50 per mile Labor was $2.25 

 per day, four-horse teams $6 to $6.50 per day, and six-horse teams $8.50 per day. 



OIL-GRAVEl KOADS 



Santa Maria, Cal. — The work at Santa Maria, Cal., consisted of surfacing with 

 oiled gravel a section of the Geary road, 2,710 feet in length and 16 feet wide. The 

 surface of the road was a sandy loam which had been oiled several times with crude 

 oil, and was badly rutted and full of "chuck holes." The oiled surface was broken 

 up by spiking with a roller, scarifying, and harrowing with a chisel-toothed harrow and 

 a disk harrow. The road was then shaped with a road grader and 1,137 cubic yards of 

 gravel were spread upon the road in two courses, 5^ and 3 inches in thickness. The 

 average cost of the gravel was $1,683 per cubic yard, which included loading on fiat 

 cars, shipping a distance of 35 miles, hauling an average distance of 1 mile, spreading 

 upon the road, rolling, and sprinkling. 



The crude oil was aj^plied at the rate of 1 gallon per square yard on the foundation 

 course, 1 gallon per square yard on the second course, and one-fourth gallon per square 

 yard on the surface. The oil was secured from the county sump. Waste oil from the 

 oil fields floats on the surface of the small streams, which are diverted to the sump, and 

 the only expense of the oil is that of collecting, heating, and pumping into tank 

 wagons. With labor at $2 to $2.50 per day and teams at $4 per day, the total cost of 

 the road to the community was $2,613.68, which is at the rate of 54.2 cents per square 

 yard, or $5,087.57 per mile. 



macadam roads. 



Carlsbad, N. Mex. — La Huerta-Avalon road. — The work of surfacing a road 1,600 

 feet in length at Carlsbad, N. Mex., was started on June 7, 1909, and the road was 

 entirely completed July 2, 1910. The road was first thoroughly irrigated, after which 

 the necessary excavation and shaping were done. Gypsum was then spread on the 

 road in three courses to a width of 16 feet and to a total depth of 9 inches. Each course 

 was rolled with a 4-ton horse roller. After the material had been spread, the road 

 was flooded from an irrigation ditch for forty-eight hours. The road and shoulders 

 were then reshaped with a road grader and rolled until a smooth, hard surface was 

 obtained. The total cost of the work was $1,144.67. The cost of the several items of 

 work was as follows: Foreman, $66; excavation and shaping, $53.50; stripping, quarry- 

 ing, and loading 1,080 cubic vards of gvpsum, $486.98; hauling 1 mile, $428.12; spread- 

 ing, ."579.97; irrigating, $7; roiling, $23."] 0. 



Resurfadwi section of La Jluerla road. — A section of the La Huerta road, 900 feet in 

 length, which was surfaced with gypsum several years ago, was resurfaced. All the 

 loose material and detritus were removed from the surface by scraping and sweeping. 

 Gypsum was then spread to a depth of 3 inches and all depressions were filled. An 

 embankment 10 inches high was then built along each shoulder and the road was 

 flooded from an irrigation ditch for thirty-six hours. The usual traflic was main- 

 tained on the road during the flooding. The water was then drained away and the 

 roadway and shoulders were shaped with a road grader and rolled with a 4-ton horse 

 roller. The new material was found to be firmiy bonded to the old surface. The 

 total cost of the work was $167, which is at the rate of $979.70 per mile. 



Surfacing Green and Tax streets. — The work of surfacing Green and Tax streets was 

 carried on in a manner similar to that of the La IIuerta-Avalon road, except that the 

 gyp.<um was put on 8 inches deep, and river Hand 2 inches in thickncs-s was spread and 

 mixed with the top course of the gypsum. A section 1 ,415 feet long and 40 feet wide 

 was surfaced at a cost of .^704. 43, wluch is at the rate of 28 cents per square yard. The 

 cost of labor was $1.75 and of teams $3.75 per day of nine hours. 



Greenville, S. C. — The work at Greenville, S. C, consisted of grading, surfacing 

 with water-bonded macadam a section of road 3,300 feet in length and 12 feet wade, 

 and surfacing with bituminous macadam a section of road 500 feet in length and 12 feet 

 wide. To secure proper grades and drainage, 3,201 cubic yards of earth were moved 

 an average distance of 700 feet in slat-bottom farm wagons, at a cost of $412.75, or 



