24 BULLETIN 300, U. S. DEPAETMENT OF AGRICULTURE. 
A rotary drag-line excavator with a 2^-yard bucket and 65-foot 
boom, mounted on skids and rollers, was used in the excavation of 
222,500 cubic yards in South Dakota. The power was obtained from 
a 50-horsepower internal-combustion engine, using gasoline. The 
cost of the machine, complete, was $10,500. The total time of con- 
struction was 148 working days, or approximately 6 months, of which 
23 days were occupied in making repairs. Two shifts of 11 hours each 
were run. The soil was a loam underlain by clay. The crew and 
rates per month were as follows: One superintendent, $125; 2 crane- 
men, at $100; 4 trackmen, at $50; 1 teamster, $45; 1 cook, $40. 
The operating expenses were as follows : 
Gasoline, 15,444 gallons, at SO. 124 SI, 915. 05 
Labor 3,060.00 
Subsistence 561. 81 
Cables 978. 87 
Repairs and renewals 845. 93 
Miscellaneous 2, 078. 72 
Interest and depreciation 2, 152. 50 
11, 592. 88 
Cost per cubic yard, SO. 0521. 
The following costs were secured on the operation of a rotary drag- 
line excavator with an 85-foot boom, 2-yard bucket, and a 50-horse- 
power engine. The work was done on the New York State Barge 
Canal. The machine weighed 147 tons and cost $10,000. It exca- 
vated earth 90 feet from center on one side and deposited it 100 feet 
from center on the other. It dug a channel 25 feet deep and deposited 
the material on waste bank 15 to 25 feet high. The material was a 
stiff clay, with few stumps or bowlders. The following is a condensed 
cost record for 5 months' work: 
Month. 
Total ex- 
pense for 
month. 
Yards ex- 
cavated 
during 
month. 
Average 
cost per 
yard. 
April 
SI, 088. 21 
1,041.53 
1,152.04 
1,317.61 
1,535.36 
5,205 
18,365 
25,333 
33,055 
47,363 
SO. 209 
.0568 
June 
.0455 
July 
.0399 
August 
.0324 
Average cost per yard for 5 months, including all charges, $0.0474. 
In May, items of cost were as follows: 
Engineer, at $90 per month 
Engineer, at $95 per month 
Fireman, pumpmen, watchmen, etc., at $1.75 per day 
Coal, at $3 per ton 
Repairs, including labor and material 
Interest and depreciation 
S90. 00 
84.04 
363. 00 
147.00 
15.82 
341. 67 
Total 1,041.53 
