to be done.

[Illustration: Fig. 10. Sectional View of Taper Attachment]

Taper attachments, like lathes, vary some in their construction, but all
operate on the same principle. An improved form of taper attachment is
illustrated in Figs. 9 and 10. Fig. 9 shows a plan view of a lathe
carriage with an attachment fitted to it, and Fig. 10 a sectional view.
This attachment has an arm _A_ on which is mounted a slide _S_ that can
be turned about a central pivot by adjusting screw _D_. The arm _A_ is
supported by, and is free to slide on, a bracket _B_ (see also sectional
view) that is fastened to the carriage, and on one end of the arm there
is a clamp _C_ that is attached to the lathe bed when turning tapers. On
the slide _S_ there is a shoe _F_ that is connected to bar _E_ which
passes beneath the toolslide. The rear end of the cross-feed screw is
connected to this bar, and the latter is clamped to the toolslide when
the attachment is in use.

When a taper is to be turned, the carriage is moved opposite the taper
part and clamp _C_ is fastened to the bed; this holds arm _A_ and slide
_S_ stationary so that the carriage, with bracket _B_ and shoe _F_, can
be moved with relation to the slide. If this slide _S_ is set at an
angle, as shown, the shoe as it moves along causes the toolslide and
tool to move in or out, but if the slide is set parallel to the carriage
travel, the toolslide remains stationary. Now if the tool, as it feeds
lengthwise of the work, is also gradually moved crosswise, it will turn
a taper, and as this crosswise movement is caused by the angularity of
slide _S_, different tapers are obtained by setting the slide to
different positions.

By means of a graduated scale _G_ at the end of slide _S_, the taper
that will be obtained for any angular position of the slide is shown. On
some attachments there are two sets of graduations, one giving the taper
in inches per foot and the other in degrees. While tapers are ordinarily
given in inches per foot on drawings, sometimes the taper is given in
degrees instead. The attachment is set for turning tapers by adjusting
slide _S_ until pointer _p_ is opposite the division or fractional part
of a division representing the taper. The whole divisions on the scale
represent taper in inches per foot, and by means of the sub-divisions,
the slide can be set for turning fractional parts of an inch per foot.
When slide _S_ is properly set, it is clamped to arm _A_ by the n