As a preliminary to describing the new Knox system of quarrying, which
even yet is not universally known among quarrymen, Mr. Saunders gives
the following in regard to older methods:

The Knox system is a recent invention; no mention was made of
it in the tenth census, and no description has yet been given
of it in any publications on quarrying. The first work done by
this method was in 1885, and at the close of that year 2
quarries had adopted it. In 1886 it was used in 20 quarries;
in 1887 in 44, in 1888 in upward of 100, and at the present
time about 300 quarries have adopted it. Its purpose is to
release dimension stone from its place in the bed, by so
directing an explosive force that it is made to cleave the
rock in a prescribed line without injury. The system is also
used for breaking up detached blocks of stone into smaller
sizes.

Quarrymen have, ever since the introduction of blasting, tried to
direct the blast so as to save stock. Holes drilled by hand are seldom
round. The shape of the bit and their regular rotation while drilling
usually produce a hole of somewhat triangular section. It was
observed, many years ago, that when a blast was fired in a
hand-drilled hole the rock usually broke in three directions,
radiating from the points of the triangle in the hole. This led
quarrymen to look for a means by which the hole might be shaped in
accordance with a prescribed direction of cleavage.

The oldest sandstone quarries in America are those at Portland, Conn.
It was from these quarries that great quantities of brownstone were
shipped for buildings in New York. The typical "brownstone front" is