Cord-Driven Semicircle Mechanisms and an Interlace Knot

Separated-semicircle device: a and b trade paths

In the central device of separated semicircles, pulling c sends a along the path a n b while b runs the path b n a. The motion reverses on the return when d is pulled instead.

United device that rewinds its cord

In the joined device at the foot, when q reaches b the point b will stand at r. The cord c g q then lies entirely at h, while the cord K fixed at b is rewound at d S r.

A device set on the embankment

One figure below is placed on the embankment (sull'argine). It is pulled backward and, in retreating, leaves the work already done in front of it.

Pulling a returns m to n

On the right-hand semicircle, labelled n - a - m, pulling a makes m return to n. On the companion left semicircle the pull of a instead drives n across to m.

An interlace knot in the corner

A small decorative interlace knot, of the looping band type Leonardo often drew, is sketched faintly in the lower-right corner of the sheet, apart from the mechanical diagrams. It carries no transcribed text.

Dal margine superiore. Figura con:

Figura sottostante, con:

A destra, semicerchio sinistro del dispositivo, con:

Semicerchio destro, con:

A sinistra, quattro figure, con:

Al centro, dispositivo a semicerchi separati, con:

In basso, dispositivo unito, con:

From the upper margin. Figure with:

Figure below, with:

On the right, the left semicircle of the device, with:

Right semicircle, with:

On the left, four figures, with:

At the center, a device of separated semicircles, with:

Below, a united device, with: