On the Moving Body and Its Mover: Kinds of Motion

Seven kinds of motion between mover and moved

Leonardo argues that the motions of moving bodies are infinitely variable from the motion of their mover, but never occur without it. He then classifies the cases: equal motion along the same line; longer or shorter motion along one line or parallels; contrary straight motion (east against west); and transversal motion at right, acute and obtuse angles.

Cord with ends m and o each bearing two pounds

Beside a lower-left figure a note explains that the end m of the cord sustains two pounds and the end o sustains two others, while n pushes toward the central line only by one. It is a study of how loads on a cord resolve against a central axis.

Friction four times weaker; simple versus compound motion

Above two figures Leonardo notes that the power of friction at b is four times less than at a. He labels a b a simple motion and n m f a compound motion, distinguishing single-line movement from a path built of several components.

Motion lengths along one line or parallel lines

A margin note states that for one same aspect the motion can be longer, equal, or shorter than the mover's. The equal and the shorter may run along one same line, but the longer of the mover cannot share one line and aspect and must instead run along parallel lines.

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Nel margine destro del foglio:

Figura con lettere.

In basso a sinistra figura con lettere:

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Figura con lettere.

A lato della figura:

Due figure con lettere.

Sopra le due figure:

Gruppo di figure, di cui due con lettere.

Tre figure.

A lato delle figure:

Tre figure.

A lato delle figure:

In the right margin of the sheet:

Figure with letters.

Lower left, figure with letters:

Figure with letters.

Beside the figure:

Two figures with letters.

Above the two figures:

Group of figures, two of them with letters.

Three figures.

Beside the figures: