[TRINGTON.l 
OPEN-CUT MINTNG. 
75 
nd not permanent frost. Had the attempt been made to work the 
round at that time with the shovel the operations would have been 
Teatly delayed. In PI. XI, A, one of the frequent defects of the 
team-shovel system is apparent— the shovel idle and waiting- for cars, 
n this plant, after the shovel had worked to a considerable distance 
rom the bottom of the incline, the li-yard cars, 3 in number, were 
rammed to the bottom of the incline by horses and hoisted to sluice 
y a I5-horsepower hoist. The tramming may be more cheaply 
ecomplished, where there are several years' work ahead, by a small 
x'omotive in the pit running to the bottom of the incline or, under 
ivorable conditions, directly to the washing plant. Fig. 10 shows a 
Ian of the operation under discussion. 
The tramming system illustrated by tig. 11, used at Galesburg, 111., 
i one of the shale pits of the Purington Paving Brick Company, is 
ansidered highly economical in steam-shovel work. As may be 
w 
I5°cable inch 
Spring switch 
"'"--■*.•.. 
Hopper No. I 
2 cars taken each time 
by incline 
Switch to R R track 
30 abore pit 
Incline 150' long 
4empty J 
ready for hopper No. t 
I when filled go to hopper No. 2 
mlum i fan i i i im i ini nam 
Locomotive 
I 90-ton steam shovel 
Fig. 11.— Plan of steam-shovel operations, Galesburg, 111. 
3en, the locomotive occupies a position intermediate between the 
vo trains of cars, which deliver two ways to the bottom of two 
lclines leading to the hoppers of the clay machines at each end 
i the pit. In placer operations, if conditions admit of dividing 
le water to two washing plants, this system is to be recom- 
lended, as it allows of rapid delivery of the cars from the shovel. 
p. this plant the locomotive keeps 20 cars goin^, each of 2 
ards capacity, tramming them alternately, in trams of 6 and 4, 
wo ways to the ends of the pit, whence they are hauled, two at a 
pie, to the hoppers. When empty they run down and are switched 
pomatically to the empty tracks. The 90-ton shovel, of 5-}^ard dip- 
pr capacity but fitted with 2-yard dipper, is ahead of the capacity of 
|e clay machines, but must be used owing to the difficulty of digging 
e firm shale which composes the bank. The actual yardage moved, 
rking nine hours a day, is 670, or at the rate of 1,488 yards in 
