Daily Arizona silver belt. (Globe, Gila County, Ariz.) 1906-1929, 1908-01-16

tically every mining distritc Of any con-
sequence, as well as in quarraying dis
tricts and in the immediate environs of
the largest cities where heavy contract
work is done. In such cases the in
stallation of an Electrician Drill
plant means simply the closing of a
contract with the power company and
the running in of supply lines to which
the cables can be connected. Before
the advent of this drill, rock drilling
on this basis with the old drill would
have meant the purchase of an electric
or steam.driven air compressor, the lay
ing off of series of pipe lines, the
placing of several air-receivers or tanks,
and the employing of at least one ex-
ira attendant at the compressor. This
is all done away with now since the new
drill is so simple that the drill runner
himself can attend to the whole thing.
In the city contracting field the use
of this drill enables the small contractor
to put an "Electric-Air Drill" at work
on a small job with no initial invest
HltHI DtNOHu tudI VI tht Vim Vutht ~
self, rush the work through in one-fifth
to one tenth the time that it would take
him by hand, and load his output on
truck for transportation to his next con-
tract job. He has no fuel to buy, no
boiler for a licensed man to fire, no
compressor to call for an engineer, no
pipe lines to lay down and take up,
and when he has paid his power bill,
and his labor for running the drill and
sharpening the steels, he has covered
the whole proposition so far as the rock
drilling is concerned.
Comparison Of Results.
1t is not often possible TO get an ex.
act comparison of costs between new
machine and an old, since the condi-
tions are very had to duplicate. Re
Gently, however, test of several
months was made in the Joplin lead
and zinc district of Missouri, where the
drilling problem is VIGOROUSLY hard. A
standard 3 IA inch air drill was run
side by side with an Electrician
Dill'' Of the same rated capacity for
| two months. At the end of this time
| the air drill had bored 1928 feet of hole
at a power cost of SEES per shift or
1925 per 100 feet of hole. Under ex.
aetly the same conditions, the 'Elec-
| tric Air Drill made 240S feet of hole
at a cost of 60 -I2 cents per shift,
/ or $l.2l per 100 feet. While the air
drill made only 35 feet per shift, the
" Electrician Drill " made so feet. In
other words, on exactly the same class
| of work the Electrician Drill y
saved four-fifths on power cost and one.
third on labor cost as compared TO the
familiar with drilling conditions will
appreciate what tremendous advance
this represents in rock drilling work,
| In another case mine shaft was
sunk 67 feet with the Electrician
Drill" in "a shifts at a power cost
of $1.00 per shift, and not cent for
repairs. In another case, tunEel7x7R
feet was driven 1929 feet in eleven
months with the Electrician Drill
at cost of $l3 per foot. Under similar
conditionsf fair cost for this work
with the ordinary air drill would be
SIS to $50 per foot.
Dozens of other instances might be
cited showing where the newer drill
had saved time and money over the
old machine but this is enough TO show
that the Electrician Drill y is not an
experiment but something which the
rock drilling public must reckon with
in the future.
FUSED at the Old Dominion Quarry
1t is said that FIVE horsepower elec
trio motor is drilling Is to 20 foot holes
at this quarry that would require e
horsepower to do with the old compress
ed air type of rock drill.
An unusual thing in connection will
the new drill is that while it would
appear on the face Of it to be a strong
competitor of the air and steam drill
and in fact a dangerous opponent OF
the latter, it is in reality being built
and sold by the company which is the
largest builder of drills of the older
type in the world. This somewhat
anomalous condition is TO be explained
by the fact that in the final analysis
the line of distinction between the two
types of machine is clearly drawn. OBJ
viously the Electrician Drill outf.
is more expensive than the single rock
drill, but the rock drill must have its
steam boiler or air compressor. On a
job which would use only one or two
or three drills, and where electric pow
err is available, it may be believed that
it is nice problem to decide which is
the more economical outfit, considering
all the requisites of complete equip
ment. But the makers, owing to their
large experience, are enabled to fix the
limiting point clearly where the condi-
tons are known, and it is found in
reality that for each particular drilling
Job it is not difficult to decide whether
the air drill or the Electrician Drill -
should be used to give the best results.
OF course, in mining districts where
fuel is costly and electric power car
be economically bought, there can oe
no doubt that the Electrician Drill y
is the better proposition as comps red
to the air drill and compressor outfit,
particularly where high attitudes and
long hauls initiate against the older
49, o,,4CA D,,t ,aplar tba orl; "