EXCAVATING MACHINERY USED IN LAND DRAINAGE. 27 



on small ditches in Iowa. The machine is of the revolving type. It 

 is equipped with a three-fourths-yard dipper and a 28-foot boom. 

 The power is derived from a 6-horsepower gasoline hoisting engine 

 geared to three hoisting drums, one of which hoists the end of the 

 dipper, one hoists the boom, and one pulls the machine ahead. The 

 machinery is mounted on a platform which revolves upon a turntable 

 supported on two wooden beams which straddle the ditch. The 

 beams rest on wooden wheels, the entire span being 22 feet. The 

 dipper handle, instead of moving forward and backward in the boom, 

 is pivoted. The entire machine weighs only about 17,000 pounds and 

 costs about $1,200. 



This excavator has dug as high as 400 cubic yards a day, but aver- 

 ages about 200 cubic yards. It can excavate a ditch with a 20-foot top 

 and can dig 13 feet deep, but 6 or 7 feet is the best working depth. Two 

 men can erect the machine in 2\ days and dismantle it in one-half 

 day; it makes about 7 wagon loads. The hoisting apparatus, which 

 is the heaviest part of the machine, weighs 4,100 pounds. The exca- 

 vator is moved ahead by means of a "dead man" and cable, and can 

 be moved across country at a speed of about 1 mile per day. The 

 machine can take out 5 shovel-loads in 2 minutes, and has dug 

 through 6 inches of frost. Only 2 men are required to operate it — 

 1 operator and 1 trackman. 



A ditch constructed by this machine in Iowa had an 18-foot top, 

 4-foot bottom, and 6^-foot depth. From 8 to 10 gallons of gasoline, 

 costing 16 \ cents at the works, were used per day. The material, 

 which was a loam underlain by a stiff gravelly subsoil, was excavated 

 at the rate of about 200 cubic yards in 10 hours. The cost of opera- 

 tion per shift was as follows : 



One operator $4. 00 



One trackman 2. 00 



Ten gallons gasoline, at $0.16J 1. 65 



7.65 



The cost per cubic yard, exclusive of interest and depreciation, 

 was about 3.8 cents. The contract price on 5,000 cubic yards was 

 12 cents. 



Such a machine as this would be well adapted to digging the small 

 ditches in the South that are almost universally put in by hand at a 

 cost of about 25 cents per cubic yard. Even in ground covered with 

 stumps, by using plenty of dynamite this type of excavator could be 

 used to advantage in reducing the cost of small ditches. 



In general, it may be said that the dry-land dipper dredge, though 

 applicable to certain conditions, has no extensive use in drainage 

 work, as excavation that is suitable to this machine can usually be 

 handled to better advantage by the drag-line scraper excavator. 



