lazy-tongs. To the joints of these the ends of racks are pinned; and as
they are stretched out the racks are moved forward 0 to 9 steps, according
to the joints they are pinned to. The racks gear directly in the A-wheels,
and the figures are placed on cylinders as in the Brunsviga. The carrying
is done continuously by a train of epicycloidal wheels. The working is thus
rendered very smooth, without the jerks which the ordinary carrying tooth
produces; but the arrangement has the disadvantage that the resulting
figures do not appear in a straight line, a figure followed by a 5, for
instance, being already carried half a step forward. This is not a serious
matter in the hands of a mathematician or an operator using the machine
constantly, but it is serious for casual work. Anyhow, it has prevented the
machine from being a commercial success, and it is not any longer made. For
ease and rapidity of working it surpasses all others. Since the lazy-tongs
allow of an extension equivalent to five turnings of the handle, if the
multiplier is 5 or under, one push forward will do the [v.04 p.0974] same
as five (or less) turns of the handle, and more than two pushes are never
required.

[Illustration: FIG. 3.]

The _Steiger-Egli_ machine is a multiplication machine, of which fig. 3
gives a picture as it appears to the manipulator. The lower [Sidenote:
Multiplication machines.] part of the figure contains, under the covering
plate, a carriage with two rows of windows for the figures marked ff and
gg. On pressing down the button W the carriage can be moved to right or
left. Under each window is a figure disk, as in the Thomas machine. The
upper part has three sections. The one to the right contains the handle K
for working the machine, and a button U for setting the machine for
addition, multiplication, division, or subtraction. In the middle section a
number of parallel slots are seen, with indices which can each be set to
one of the numbers 0 to 9. Below each slot, and parallel to it, lies a
shaft of square section on which a toothed wheel, the A-wheel, slides to
and fro with the index in the slot. Below these wheels again lie 9 toothed
racks at right angles to the slots. By setting the index in any slot the
wheel below it comes into gear with one of these racks. On moving the rack,
the wheels turn their shafts and the figure disks gg opposite to them. The
dimensions are such that a motion of a rack through 1 cm. turns the figure
di