has taken place, a
proper adjustment of the lathe saddle becomes impossible if the job is
a long one. In the case of raised Vs, however, the wear simply causes
the saddle to fall vertically, so that an amount of wear equal to
1/100 of an inch would have the same effect as lowering the tool 1/100
inch, its effect upon the work being almost imperceptible by ordinary
measurement. On the other hand, however, V lathes are usually made
with either a weight or a spring to keep the saddle down; and as a
result, when the cutting tool stands far out from the tool post, the
saddle is apt to tip, especially in the case of boring with a lathe
tool. In some cases, the raised Vs are accompanied with gibs to secure
the saddle; but in many instances the gibs are given too little
wearing surface. In the lathe above referred to, there are three ways
in one casting, with the slide angles on the outer edges. There are
also three separate and independent tail stocks fitting into the two
openings between the ways. The running head has one cone pulley
connected by suitable gearing to three face plates. The three centers
at the running head are stationary. The slide rest saddle spans the
three ways, having a V slide which contains three separate slide
rests, all connected by a nut to the feed screw, so that all three are
operated by the one screw. In addition to this, the two back slide
rests have the nuts so attached that they can be moved by means of a
separate screw, the object being to facilitate setting the cuts, since
it would be a tedious matter to set all three tools to an equal cut,
or to their desired respective cuts, without means of operating two of
them independently. To set the cut during screw-cutting operations,
the ingenious device shown in our engraving is provided. A represents
the cross-feed or slide rest screw, which operates the three slide
rests. It is fast to the notched wheel, B, and is operated by it in
the usual way. C is a short screw which provides journal bearing for
the screw, A, by a plain hole. It is screwed on the outside, and the
plate in which it fits acts as its nut. It is fast to the handle, D,
and is in fact operated by it. The handle or lever is provided with a
catch, E, pivoted in the enclosed box, F, which also contains a means
of detaining the catch in the notches of the wheel, or of holding it
free from the same when it is placed clear. If, then, the lever, D, be
moved back and forth the feed screw, A