718 ANNUAL, REPORTS OF DEPARTMENT OF AGRICULTURE. 



COMPLETED ROADS. 

 BITUMINOUS-MACADAM ROADS. 



RocKroRT, Me. — During the interval from August 20, IDIO, to October 13, 

 iniO, engineers from this office were in charge of the construction of a portion 

 of a bituminous-macadam road running from Rockland to Rockport. This road 

 is a trunk-line StJ'.te road built by the Maine State highway department. Its 

 total length is 23,772 feet, and the construction was let by contract for $:)5.700, 

 but this price did not include the bituminous binder. The .stone was a rather 

 soft limestone. It was crushed and screened at the quarry and hauled directly 

 to the roadside by the local electric railway company. It cost 75 cents per ton. 

 On October 14, 14.500 feet of this road had been graded and about 13,500 feet 

 surfaced with stone. The road had been completely finished for a distance of 

 32.120 feet. The following data as to the costs of bituminous treatment were 

 obtained: Total amount applied per square yard, 2.21 gallons; cost of applying, 

 1.25 cents per gallon; rolling, 1.14 cents per square yard; and foreman. 1.53 

 cents i)er square yard. The item of applying tar includes the cost of filling the 

 kettle, heating, and pouring. Three varieties of tar products were applied by 

 the penetration method. All were delivered in 50-gallon barrels, heated in 

 kettles, and spread by hand with pouring pots having fan-shaped nozzles. The 

 cost of spreading the stone, including the spreading of the chips on the tar 

 courses, was 20.97 cents per ton. As the contract price for this road was at 

 the rate of $7,030 per mile, exclusive of bituminous material, the total cost to 

 the community per mile would be obtained by adding the cost of the bituminous 

 material, which, at approximately 24 cents per square yard, would be $1,970, 

 making the total cost per mile $9,900, or approximately $1.20 per square yard, 

 for the 14-foot bituminous-macadam surface. The road, however, was graded 

 20 feet wide, and the above cost includes all grading and drainage incidental to 

 the work. 



Westminster, Md. — The work at Westminster, Md., consisted in resurfacing 

 5,650 feet of Main Street with bituminous-macadam. The work began on 

 August 1, 1910, and was completed on October 18, 1910. The stone used included 

 trap, gneiss, and limestone. In preparing the subgrade 2,000 cubic yards of the 

 old surface were excavated, screened, and relaid. The binder was applied by 

 the penetration method, using a refined water-gas tar and an oil-asphalt, both 

 of which were furnished in accordance with specifications drawa by this office. 

 It cost $27.75 to spike the old surface with a roller, $136.50 for plowing, $320.75 

 for screening, $341 for hauling the waste material, $217.25 for hand picking, 

 $272 for hauling, and $62.25 for spreading; and 3.190 tons of crushed stone were 

 purchased at a total cost of $4,478.50. Hauling this stone cost $026 and spread- 

 ing $131.25. For the bituminous work proper the following were the items of 

 cost: 47,300 gallons of bituminous binder, $3,325.75; heating the material, 

 $180.25; hauling it, $94.50; applying it, $110.50; rolling it, $34; and spreading 

 the chips, $78.75. 



The total cost of this road to the community was $11,618.25, which is at the 

 rate of 56.6 cents per square yard, or $10,558 per mile. These figures were based 

 on a labor cost of $1.50 per day of 10 hours, teams at $3 per day, and fuel at $4 

 per ton. The work comprised 20,500 square yards. 



Knoxville, Tenn.— a section of the Rutledge Pike, beginning at the old 

 schoolhouse and running northeast to Lake Street, was selected for this work. 

 The section is 980 feet in length. Work was begun on July 25, 1910, and fin- 

 ished on September 7, 1910. 



The old macadam surface was first spiked up with a road roller, equipped 

 with spikes, and brought to a true grade with a I'oad machine and slips. A 

 spike-tooth harrow was used to bring the coarse stone to the surface and work 

 the fine material down. Crushed limestone was then spread over the surface in 

 a 2-inch layer aijd rolled until firm. For the bituminous wearing surface a 

 harder, close-grained rock, known locally as iron limestone, was used. The bitu- 

 men was applied by the penetration method, using a refined coal tar, a refined 

 tar preparation, and an oil-asphalt on three separate sections. 



Unskilled labor was used, which was figured at $1.35 per 10-hour day for the 

 foundation work and $1.50 per 10-hour day for the bituminous work. Double 

 teams cost .$3.50 per day, and roller and operator $3 per day. The limestone 

 cost $1.20 per cubic yard on the siding, and the iron limestone 67.5 cents per 



