Coal occurs underground in layers, called seams, which are sandwiched
between layers of rock deep in the earth. Most seams of coal are 5-10
feet deep, but the can cover thousands of square miles.
Coal mining in 1900 was a three-step process.
1. Undermining: "A slot 6 feet wide and 4-5 feet deep is cut into
the bottom of a coal seam ... This is generally done with a pick. The
miner stands upon his feet and strikes with all his strength, until a
few inches in depth is cut; he then sits down on the floor of the mine,
his legs stretched wide apart in front of his body, and cuts in six inches
to a foot deeper; finally, he stretches his body along the floor, his
shoulder and arm to the elbow resting upon his thigh, and in this ...
position finishes up the undermining. It will take 2 active miners 4 or
5 hours to undermine a room 8 yards wide and 4 to 5 feet in depth. 40
to 50 blows of the pick are delivered per minute ... The pick weighs 2
to 3 pounds." [Source: Ohio State University]
2. Drilling and Blasting: The miner drills holes into the face of a coal
seam. The holes are filled with dynamite. Then the dynamite explodes,
the coal crumbles and falls.
3. Loading the Coal: The coal is then shoveled into carts by the laborers
who work in pairs with the miners. The cars are pulled by donkeys that
haul it to shafts where it is taken out of the mine. The miners are required
to produce enough coal to fill about 6 carts per day. The 2 laborers who
load the carts shovel about 4 tons of coal a day. [Source: Museum of Science
and Industry www.msi.chicago.org]
Use the information about mining to answer the questions below:
1. Billy's Dad and his partner are undermining a seam of coal that is
16 feet wide, 4 feet deep, and 10 feet high.
A. Draw a scale model of the seam. Let 1 inch on the model equal 2 feet
of the seam.
B. How many cubic feet of coal would fall to the ground after they blasted
C. It took the 2 miners 3 hours to undermine this seam of coal. How many
times did Billy's Dad swing his pick before the job was done? Explain
how you got your answer.
D. About how many times will Billy's Dad swing his pick in a week if he
undermines a seam like this every day?
E. Billy is a laborer. He and his partner work with Billy's Dad. How many
pounds of coal will Billy shovel in a week?