sundry descriptions of such apparatus in the engineering papers, confine my
remarks to the more recent improvements in three great classes of machines.
These are, briefly, plain sewing machines; sewing machines as used in
factories, where they are moved by steam power; and special sewing
machines, embracing many interesting forms, only recently introduced. We
have thus to consider, in the first place, the general efficiency of the
machine as a plain stitcher. Secondly, its adaptability to high rates of
speed, and the provision that has been made to withstand such velocities
for a reasonable time. And, thirdly, the apparatus and means employed to
effect the controlling of the motive power when applied to the machines.

To deal with the subject in this way must, I fear, involve a good deal of
technical description; and I hope to be pardoned if in attempting to
elucidate the more important devices, use must be made of words but seldom
heard outside of a machinists' workshop.

It appears scarcely necessary to premise that the sewing machine of twenty
years ago has almost faded away, save, perhaps, in general exterior
appearance; that the bell crank arms, the heart cams, the weaver's
shuttles, the spring "take ups," rectangular needle bars, and gear wheels,
have developed into very different devices for performing the various
functions of those several parts.

The shuttle is perhaps the most important part of a lock stitch machine.
But what is a shuttle? So many devices for performing the functions of the
early weaver's shuttle have been introduced of late, that the word shuttle,
if it be used at all, must not be accepted as meaning "to shoot." We have
vibrating shuttles, which are, strictly speaking, the only surviving
representatives of the weaver's shuttle in these new orders of machines;
and stationary shuttles, oscillating shuttles, and revolving shuttles,