h all its intricacies,
could be sent to the United States, in the face of American
manufacturers, even though the cost was increased from 40 to 60 per
cent.? At the present time it was possible for English machinists to
secure contracts for the whole of the machinery in an American mill,
and inclusive of freight charges and high tariff, deliver and erect it
in America at a lower cost than American engineers with all the
advantages of their immeasurably superior tools were able to do.
Another speaker, Mr. Barstow, ridiculed the idea that the Americans
could be so pre-eminent in the manufacture of emery wheels as might be
inferred from Mr. Renold, when they had before them the fact that from
the neighborhood of Manchester thousands of emery wheels were every
year exported to the United States.

* * * * *

MODERN METHODS OF QUARRYING.

Mr. Wm. L. Saunders, for many years the engineer of the Ingersoll Rock
Drill Co., and hence thoroughly familiar with modern quarrying
practice, read a paper before the last meeting of the American Society
of Civil Engineers on the above subject, containing many interesting
points, given in the _Engineering News_, from which we abstract as
follows.

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 fi