EXCAVATING MACHINERY USED IN'. LAND DEAINAGE. 31 
soil. Attempts to do this have, up to this time, met with doubtful 
success. 
COST OF OPERATION. 
Two machines of the wheel type designed to cut a ditch 4 feet deep, 
4 feet wide at the top, and 2 feet wide at the bottom, were used on 
the excavation of some ditches in one of the Gulf States. Each 
machine was driven by a 28-horsepower gasoline engine. The dig- 
ging wheel was 15 feet in diameter and the 2 apron tractors each 
5 feet by 12 feet. The weight of each excavator was about 30 tons. 
The first cost of the machine was $5,500 and freight to the point of 
use was $338.36, making the total cost of each machine $5,838.36. 
The soil was a hard, yellow, sandy clay overlain by a turfy muck, 
varying in depth up to 2J feet. The turf was easily cut, but the 
hard clay caused excessive wearing on the bearings. A large part 
of the work was done when water was from 2 to 3 feet deep on the 
land. The total length of the ditches dug was 165 miles, the aver- 
age length of ditch being 2,475 feet. The average depth of digging 
was about 4 feet, with a 4-foot top and 2-foot bottom. The average 
distance dug per shift of 10 hours of actual running time was 2,250 
feet; the maximum distance dug in 10 hours was 6,600 feet. The 
average yardages per month for the two machines were 13,245 and 
13,180 cubic yards, respectively. The average daily outputs on the 
basis of the actual running time were 1,000 and 1,126 cubic yards, 
respectively. A part of the time the first machine ran a double shift, 
which accounts for the higher monthly and less daily average. It 
required 13 months to complete the work, the actual time of opera- 
tion being about half this. On account of the excessive wearing on 
the bearings, caused by the heavy sandy clay, it was necessary to 
make frequent stops for rebuilding the machines, which operation 
occupied an average of nearly two weeks. The total excavation was 
317,162 cubic yards. 
The daily operating expense per 10-hour shift for each machine was 
about as follows : 
Per day. 
One operator, at $100 per month. ........... . . - - $4. 00 
One assistant . - 2. 00 
50 gallons gasoline, at 16 cents 8. 00 
Repairs 6. 00 
Other charges 12.00 
32.00 
The itemized cost for operation for the entire work was as follows: 
Labor $5, 172. 11 
Interest, discount, and exchange. 202. 05 
Maintenance and repairs 2, 860. 08 
General expense 273. 10 
Management expense 1? 600. 00 
Provisions and cooking (cook's wages) 2, 245. 91 
