The two bellows are then laid valve
facing valve, and are attached to one another by a strip of tin passed
round the wood just behind the nozzles and by tying the two fixed handles
together.
[Illustration: FIG. 185.--Double-acting bellows. Two methods of coupling
shown.]
Make a rectangle of stout wire somewhat wider than the handles and long
enough to reach from the outer face of one moving handle to that of the
other, when one bellows is quite closed and the other full open. The ends
of the wire should be soldered together, and the ends of the link held up
to the handles by a couple of staples.
An alternative method is to use a piece of wood with a screw driven into it
at right angles near each end through the staples on the handles (Fig. 185,
a). In place of the staples you may use screw-in eyes fitting the screws.
XXXVI. A HOME-MADE PANTOGRAPH.
The pantograph is a simple apparatus for copying drawings, maps, designs,
etc., on a reduced or enlarged scale, or to the same size as the original.
[Illustration: FIG. 186.--Details of simple pantograph.]
A sketch of a pantograph is given in Fig.
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