By William N. T. Wylie
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Over time,
mechanized cutters began to supplant manual pick and blasting
techniques. Mechanical coal cutters were first introduced into
the Galt mines at Lethbridge in the 1880s in order to reduce the
high expense of skilled labour. By the early decades of the 20th
century, the shift had become quite dramatic. The proportion of
mechanically-cut coal, measured as a percentage of production,
increased in Alberta from 22.5 percent in 1913, to 40.6 in 1924,
and 44 percent in 1934.1 Most of the cutters were
punchers, small machines, acting by percussion, which were used
to undercut the coal prior to blasting. Eventually,
larger machines, utilizing teeth set in a revolving apparatus,
completely superseded pick and explosives techniques in some
mines.
The source of power for the
machines varied. Before 1900, most of the cutters were powered
by compressed air, sent through lines coming from compressors on
the surface. Compressed air was viewed as safer than
electricity, which was feared because of the danger of sparks.
After 1900, however, electricity was increasingly used
underground, particularly in plains mines, as greater provision
was made for safety concerns, and earlier fears dissipated. The
proportion of coal cut with cutters driven directly by
electricity increased significantly in Alberta in the early part
of the 20th
century, rising from 2.8 percent in 1913 to 27.4 in 1924.2
The proportion of mechanized
cutters was much greater on the plains than in the mountains. On
the plains, the seams were flatter and the danger of
gas-potentially combustible with machinery-was relatively small.
In the steeply-inclined and gassy seams of the mountains, on the
other hand, cutters were introduced relatively late and were
usually limited to compressed air picks or punchers. While these
machines required two men to maneuver them into place, they were
small enough to fit in the tight spaces of the mountain rooms.
They did not come into common use in the Crowsnest Pass until
the 1920s and at Nordegg until the 1940s. In the Coal Branch,
mechanization was even more limited, being restricted mainly to
compressed air drills, which replaced hand augers in the 1940s.3
The challenge of underground
haulage also prompted the use of machines. After being cut, the
coal had to be moved from the rooms through the main tunnels to
the openings at the surface. The practice was to lay tracks from
the base of the chutes in the mountain mines, and from the
entrances to the rooms in the more conventional plains
operations. Coal fell into coal cars from the chutes, or was
loaded by hand, with shovels; in the prairie mines. In the early
years, the coal cars were pulled by horses, ponies, or mules
along the main entries to the surface. An exception occurred in
shaft mines where electric, or steam-driven, hoists were
employed to raise the cars in cages from the bottom of the pits.
Animals continued to be the main mode of conveyance in smaller
mines, and were employed in larger operations to work in tight
spaces, such as between the rooms, until the 1950s.4
In the larger mountain and
plains mines, animals were gradually replaced in the main
passages by mechanized systems. The process began about 1900
with the introduction of mechanical rope haulage. This system,
which became quite prevalent, depended on the installation of
wire rope, which ran for great distances underground. The rope
pulled the coal cars towards the surface by means of power
coming from hoists, usually located on the surface, and run by
electricity. Conveyors also came into use in the early 20`h
century. Widely used in plains operations, they were not
practicable in the steeply-dipping parts of mountain operations,
but could be employed in more level sections. Conveyors were
installed at Blairmore and Coleman in the Crowsnest Pass as
early as 1906. By the 1930s, they were employed at Michel and
Coal Creek in the Pass and were becoming widespread on the
prairies, especially in Lethbridge and the Drumheller Valley. By
the 1940s, mechanical loaders had also been introduced, which
scooped up the coal in the rooms and loaded it on cars or
conveyors for the journey to the surface.5
Finally, starting shortly after
1900, locomotives began to appear in the main passages of large
mines, when the slope was gradual. In the Crowsnest Pass and at
Bankhead near Banff, these conveyances were powered by
compressed air, which was relatively spark-free and hence safe. The system required a network of underground pipes
linking recharging stations along the rails, from which the
tubular-shaped tanks of the engines could be replenished. When
the danger of explosions was less, electric trolley locomotives
were employed. They were introduced in Pembina, west of
Edmonton, by World War One, and in the Drumheller Valley by the
1930s. Battery-powered locomotives also were used between the
rooms of the Atlas mine in the Drumheller Valley by this time.
Finally, diesel locomotives were introduced in the Crowsnest
Pass in the late 1940s, and at Lethbridge by 1950.6
The underground passages also
contained provisions for drainage and ventilation. Gravity was
employed to expedite drainage at mines with drift entrances,
since the nearly-horizontal passages were constructed to slope
slightly down towards the openings. As mines expanded, and
internal slopes or vertical shafts were constructed, compressed
air or electrically-driven pumps were placed in the tunnels at
strategic locations to get rid of the ground water. The layout
also was designed to facilitate ventilation. From the entries to
the face, the tunnel system has been constructed in the form of
pairs of parallel passages. There was a natural tendency for air
to move from the inlet entry through the mine and back to the
outlet tunnel by means of convection currents responding to
different temperatures on the surface and underground. The
process was facilitated by a series of underground partitions
and doors, or "traps", which channeled the air in the required
directions. To supplement the flow of air, underground furnaces
were at first built in the upcast shafts of some mines in the
Crowsnest, and elsewhere, to heat the air and speed the process
by which warm air was expelled and new air was drawn in. This
practice was extraordinarily dangerous in gas-laden air, and had
been discarded by the First World War. Instead, large
electrically-powered fans were becoming common at many mines.
Situated on the surface, they either sucked air out of the
outlet tunnel, or pushed fresh air into the inlet entry.7
William N.T. Wylie, "Coal-Mining Landscapes: Commemorating
Coal Mining in Alberta and Southeastern British Columbia," a
report prepared for the Historic Sites and Monuments Board of
Canada, Parks Canada Agency, 2001.
See Also:
The Coal
IndustryOverview, Rapid Expansion,
Domestic and Steam Coalfields,
1914-1947: The Struggling Industry,
Collapse and Rebirth,
Settlement of the West,
Issues and ChallengesOverview,
Entrepreneurship, Technology,
Underground Techniques,
Surface Technology,
Surface Mining,
Social Impacts,
Unions,
1882-1913: Unionization and Early Gains,
1914-1920: Revolutionary Movement,
1921-1950s: Labour Unrest and
Setbacks, Mining Companies, People of
the Coal Mines,
The Middle Class,
Miners and Local
Government,
Politics and Economics ,
Environmental Impacts,
Health and SafetyOverview,
The State and
Labour Relations,
The State and
Development after 1918
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