e and either the cutter or the part being machined is
given a feeding movement, depending on the character of the work. The
spindle can be moved in or out by hand for adjustment, or by power for
feeding the cutter, as when boring or drilling.

[Illustration: Fig. 1. Lucas Horizontal Boring, Drilling and Milling
Machine]

The entire spindle-head _H_ can also be moved vertically on the face of
the column _C_, by hand, for setting the spindle to the proper height,
or by power for feeding a milling cutter in a vertical direction. When
the vertical position of the spindle-head is changed, the outboard
bearing block _B_ also moves up or down a corresponding amount, the two
parts being connected by shafts and gearing. Block _B_ steadies the
outer end of the boring-bar and the back-rest in which this block is
mounted can be shifted along the bed to suit the length of the work, by
turning the squared end of shaft _D_ with a crank. The platen _P_ has a
cross-feed, and the saddle _E_ on which it is mounted can be traversed
lengthwise on the bed; both of these movements can also be effected by
hand or power. There is a series of power feeding movements for the
cutters and, in addition, rapid power movements _in a reverse direction
from the feed_ for returning a cutter quickly to its starting position,
when this is desirable.

This machine is driven by a belt connecting pulley _G_ with an overhead
shaft. When the machine is in operation, this pulley is engaged with the
main driving shaft by a friction clutch _F_ controlled by lever _L_.
This main shaft drives through gearing a vertical shaft _I_, which by
means of other gears in the spindle-head imparts a rotary movement to
the spindle. As a machine of this type is used for boring holes of
various diameters and for a variety of other work, it is necessary to
have a number of speed changes for the spindle. Nine speeds are obtained
by changing the position of the sliding gears controlled by levers _R_
and this number is doubled by back-gears in the spindle-head and
controlled by lever _J_.

The amount of feed for the spindle, spindle-head, platen or saddle is
varied by two levers _K_ and _K_{1}_ which control the position of
sliding gears through which the feeding movements are transmitted. The
direction of the feed can be reversed by shifting lever _O_. With this
particular machine, nine feed changes are available for each position of
the spindle back-gears, making a total of eig