UKiNGTON.] OPEN-CUT MINING. 81 
iall3 r along- the stream, the sluice boxes being" moved every three or 
bur days, following the progress of the shovel. This practice alone 
nvolves both good and bad features. The practice of dumping 
lirectly into the sluice is, theoretically, much to be desired, embody- 
ng, as it does, only one elevation of the gravel, an arrangement which 
onsumes the least power and time — two all-important factors. The 
Qoving of the sluice boxes, however, in this case consumes much 
inn — from one to two days for each move — and, wages being $6 a 
lay and the season very short, constitutes a serious drawback, greatly 
educing the capacity of the plant. The boom of the machine, as 
tated, is 50 feet long and hoists the gravels 30 feet above the cut. If 
n arrangement facilitating the moving of the boxes could be devised, 
o as to avoid the long delays caused by this operation, a very satisfac- 
ory result might be effected. Such a system requires a relatively 
hallow bank, however, and it is doubtful whether it is available for 
team-shovel operations in general. 
In this instance the gravel to be taken out is frozen, and continuous 
hawing must accompany the advancing work. In this work 15 steam 
joints are driven into the bank to bed rock, where the}" remain 
wenty-four hours, the process consuming during that time 3 cords of 
r ood. A 25-horsepower boiler is used for this duty. (See PI. XIII, B.) 
Water is very scarce at this plant and is used repeatedly, being raised 
fom the pit by a centrifugal pump and carried back to the sluice 
oxes in a flume. The pump also serves to drain the pit. The sluice 
oxes have a grade of 9 inches to 12 feet, but, with the water at hand, 
re unable to keep pace with the capacity of the machine. 
I The shovel carries a one-yard dipper operated by chains. It is 
aimed that 1 cubic yard is moved every two minutes. Bed rock of 
slaty nature is taken up to a depth varying from 2 to 5 feet. 
The problem of disposal of tailings is a difficult one and has not 
3en solved economically. A steam scraper is used and all tailings 
ust be scraped to one side and elevated. Not only is the expenditure 
t wood an item, but a man must be constantly attending the scraper 
hile another handles the steam winch. 
A tramming system which would convey the material to be washed 
I such a point as would admit of the disposal of tailings by gravity, 
|en if a thousand feet or more distant, would be a more economical 
irangement, saving, as it would, not only all elevation of tailings, 
lit also all delay in moving the washing apparatus. 
Ten men are employed about the plant each shift, occupied in 
sraping tailings, forking gravel in dump box, running shovel, 
Blending steam points, and in cleaning bed rock at places where the 
coper could not effectually work. 
Bull. 263—05 6 
