Quadrature studies: lunes and proportional circles

A triangle equal to the remainder of the semicircles (n a b m)

The triangle a b, once the two portions n m are taken away, is worth the remainder of each semicircle from which the value of the two greatest portions n m is drawn. Therefore half of the triangle a b is worth half of that remainder.

Circles in quadruple proportion

Of circles quadruple to one another, the quarter of the greater is worth the whole of the lesser, so the eighth of the greater is worth half the lesser. Hence the portion of the quarter part of the greater equals the four portions of the lesser, and its half-portion equals the two portions of the lesser's half.

Circles sixteen times one another (s b n o c f m i h)

Of circles that are sixteen times one greater than the other, the sixteenth part of the one is worth the lesser circle, and half of the lesser circle is worth the thirty-second part of the greater. The figure is marked a b quarter, c o n eighth, h i m sixteenth.

Squaring the remainder of a square minus a circle

Leonardo plans to make a square and take a circle from it, then square the remainder, which carries the concavities of four portions. Having squared that remainder, he subtracts it from the greater square, and the remaining square is equal to the circle.

A note of 66 baiocchi

In the right margin, amid the geometry, a small money memorandum records 66 baiocchi, with a stray 6 beneath it.

A sinistra dall'alto, semicerchio con:

Due cerchi e un quadrante di cerchio con:

Figura di cerchio entro un cerchio ad esso quadruplo:

Settore di cerchio con:

A destra, settore di cerchio con:

Grande settore di cerchio con:

Sotto la grande porzione:

Continua sul margine sinistro, seguendo il tratto di penna:

Due figure con:

Verso il centro, semicerchio segnato con crocetta:

Sotto il precedente, due figure con:

A destra delle due precedenti, figura con:

Gruppo di figure, sopra la precedente, tre delle quali con:

Sul margine destro:

On the left from the top, a semicircle with:

Two circles and a quadrant of a circle with:

Figure of a circle within a circle quadruple to it:

A sector of a circle with:

On the right, a sector of a circle with:

A large sector of a circle with:

Below the large portion:

Continues on the left margin, following the pen-stroke:

Two figures with:

Toward the centre, a semicircle marked with a little cross:

Below the preceding, two figures with:

To the right of the two preceding, a figure with:

A group of figures, above the preceding, three of which with:

On the right margin: