examined the quarry till he had found a stratum
of the right thickness. He had marked where the ends were to come, and
the men had drilled holes down to the bottom of the stratum. Then he
had drawn a line at the back along where he wished the split to be,
and the men had drilled on this line also a row of holes. Next came
the blasting. If one very heavy charge had been exploded, it would
probably have shattered the whole mass, or at any rate have injured it
badly. Instead of this, they put into each hole a light charge of
coarse powder and covered it with sand. These were all fired at the
same instant, and thus the great block was loosened from the wall.
Sometimes there seems to be no sign of strata, and then a line of
horizontal holes must be drilled where the bottom of the block is to
be. After this comes what is called the "plug-and-feather" process.
Into each hole are placed two pieces of iron, shaped like a pencil
split down the middle. These are the "feathers." The "plug" is a small
steel wedge that is put between the iron pieces. Then two men with
hammers go down the line and strike each wedge almost as gently as if
it was a nut whose kernel they were afraid of crushing. They go down
the line again, striking as softly as before. Then, if you look
closely, you can see a tiny crack between the holes. There is more
hammering, the crack stretches farther, a few of the wedges are driven
deeper and the others drop out. The block splits off. A mighty chain
is then wound about it, the steam derrick lifts it, lays it gently
upon a car, and it is carried to the shed to be cut into shape,
smoothed, and perhaps polished.

In almost every kind of work new methods are invented after a while.
In quarrying, however, the same old methods are in use. The only
difference is that, instead of the work being done by muscle, it is
done by compressed air or steam or electricity. Compressed air or
steam works the drill and the sledgehammer. The drill is held by an
arm, but the arm is a long steel rod which is only guided by the
workman. Not the horse-sweep of old times, but the steam derrick and
the electric hoist lift the heavy blocks from the quarry. Polishing
used to be a very slow, expensive operation, because it was all done
by the strength of some one's right arm, but now, although it takes as
much work as ever, this work is done by machinery. To "point" a piece
of stone, or give it a somewhat smooth surface, is done now with tools