EXCAVATING MACHINERY USED IN LAND DRAINAGE. 4] 
the spud feet are 12 feet long by 8 inches wide. The bearing pres- 
sure when working is about 3 pounds per square inch. The distance 
covered at each move of the spud feet is 5 to 6 feet, and it requires 
about 30 seconds to move the machine ahead this distance. The road 
speed is 14 miles in 10 hours. About 30 gallons of kerosene are re- 
quired per 10-hour shift. For operation three men are required— 
one runner, one craneman, and one trackman. The machine can be 
shipped on one car and requires four men one day to assemble and 
the same time to dismantle. The average output is from 500 to 800 
cubic yards in 10 hours. The ditch best suited for the small ma- 
chine is one with a 6-foot top and 4 feet of depth, although it can 
dig a ditch with a 20-foot top and 12 feet in depth. The machine 
costs about $12,000 with the sliding-track mounting and $15,000 
with caterpillar mounting. 
The larger machine (Pl. VITI, Fig. 1) has a 1-yard bucket, 32-foot 
boom, and 45-horsepower engine, and weighs, complete, 45 tons. 
The track shoes are each 34 feet long by 40 inches wide, and the spud 
feet 2 feet wide and 12 feet long. The bearing pressure when work- 
ing is 2.8 pounds per square inch. The distance covered at each move 
of the machine is 5 to 6 feet, 45 seconds being required to make the 
move. The road speed is about three-fourths mile in 10 hours. 
- About 40 gallons of kerosene are required per 10-hour shift. The 
machine requires three men for operation—one runner, one crane- 
man, and one trackman. Two cars are needed to ship the machine. 
Four men can assemble it in five days and dismantle it in the same 
time. The average output is from 700 to 1,000 cubic yards per 10- 
hour shift. The size or ditch best suited for the machine has a 20- 
foot top and 7 feet in depth. It can, however, dig a ditch with a 
35-foot top and 14 feet deep. The machine costs about $18,000. 
Over dry earth roads four men with four teams have hauled the 
large machine 4 miles in three days. The smaller machine can be 
shipped already assembled, whereas the larger machine must be dis- 
mantled for shipping. 
This type of machine when digging does not straddle the ditch, 
but works along the center line when a new ditch is being dug or 
on one bank when an old ditch is being enlarged or cleaned out. No 
earth “roll” is left on the bank to fall back into the ditch. On 
these machines the average life of a loading line is 15,000 cubic yards; 
of a hoisting line, 40,000 cubic yards; of the track lines, 60,000 cubic 
yards. For the larger machines the minimum economical project is 
about 200,000 cubic yards with double-shift operation. For the 
smaller machines the job should have about 30,000 cubic yards. 
Contractors state that for the smaller machine they do not want to 
take a job costing less than $8,000. 
