Squaring the circle, a pulley, and two building elevations

Of the pulley, cords, weight and load (a, c, b)

A pulley lettered a, c, b heads a note titled "Of the pulley, cords, weight and moving load." Leonardo argues that the motor's cord feels more weight than the load's cord, because the motor's cord bears the weight of the load plus the excess by which the motor exceeds it.

Of transmutation: only the semicircle can be squared

Under the heading "Of transmutation," Leonardo states that to no portion of a circle is an equal circle given except the semicircle, while to every sector — greater or smaller than the semicircle — an equal circle can be given. It sets the programme for the surrounding figures.

The axiom: equals removed from equals leave equals

Above an inscribed square subdivided into small squares Leonardo writes the axiom that if from equal things one removes equals, the remainder stays equal. He reuses this rule again and again to reduce lunes and circle portions to squares.

Squaring a circle by its greatest portions (a, b)

A lettered circle (a, b) carries a full proof: the smaller circles being half the greater, the remainder of the greater circle equals the smaller circles, so that once the four greatest portions are taken away the remainder is squarable, and removing the two squares leaves a squared remainder.

The oval equals its two surrounding lunes

Beside one figure Leonardo notes that the oval is worth the two lunes (falcate) that surround it, and beside a similar figure that each lacks the value of the four greatest portions. These are among the concluding results of the squaring series.

Two elevations: an arcaded building and a temple front

The upper centre carries two finished pen elevations: a tall, multi-storey arcaded building with balustrade and a pedimented, columned temple front with an arched opening. They stand out from the surrounding geometric diagrams as architectural design studies.

Angolo superiore destro:

Carrucola colle lettere:

Presso il margine sinistro, tre figure di carrucole:

Al centro del margine superiore:

A sinistra, sopra la figura di quadrato iscritto e suddiviso in quadratini:

Colonna destra dopo la nota sulla carrucola. Cerchio dentato:

Figura sottostante:

Coppia di bisangoli contenuti in un rettangolo:

Anello con appendice triangolare:

Cerchio diviso in 4 settori con lunole, e piccolo cerchio con lunola e la lettera:

Doppia figura colle lettere:

Colonna successiva, sotto il disegno architettonico. Cerchio con otto bisangoli:

Cerchio colle lettere:

Sotto il secondo disegno architettonico, cerchio con 8 bisangoli:

Doppio cerchio con quattro bisangoli:

Cerchio colla lettera:

Figura sottostante:

Figura simile alla precedente:

Upper right corner:

Pulley with letters:

Near the left margin, three pulley figures:

At the centre of the upper margin:

At left, above the figure of an inscribed square subdivided into small squares:

Right column, after the note on the pulley. Toothed circle:

Figure below:

Pair of lens-figures contained in a rectangle:

Ring with a triangular appendage:

Circle divided into 4 sectors with lunes, and a small circle with a lune and the letter:

Double figure with letters:

Next column, beneath the architectural drawing. Circle with eight lens-figures:

Circle with letters:

Beneath the second architectural drawing, circle with 8 lens-figures:

Double circle with four lens-figures:

Circle with the letter: