Turn it one hour to the right and one hour to the left, and thus the curved rib and the opposite sides of the pole will wear away equally.

Go to Verzé and see the teeth of the wheels (a small figure follows), toothed on the face, with the little rackets toothed on the face, and what rule they have in driving one another. Go to Strada Solata.

6 ounces – 2 ounces wide – 2 ounces – 6 ounces – half a braccio – wheel teeth 36.

a – b

n m is one and a half braccia high, one braccio wide and half a braccio thick. Let a b exceed the clear space by half a braccio; the pinion 12 spindles within a third of a braccio; the wheel that moves this pinion should have 36 teeth and be one braccio wide.

Rule (straightedge) of the shaft.

A flat iron plate, soldered with copper, and a ring made of jeweller's glue, upon which the collar is fixed, and so it is held firm in the middle of that plate.

n – m

The raiser of the generating base of the pyramid has the motion of the mother (nut) of its screw.

a – n

The pivot a must project out beyond its support by as much as half the thickness of the little wheel n, and likewise by half the thickness of the wheel of the prime mover.

The nut made square with holes, using the jeweller's glue.

The percussion. – The derivative shadow in darkness is like the darkness of that same derivative shadow, that is, the varieties of its darkness. The further the derivative shadow removes itself from the primitive shadow, the more it differs from that primitive shadow in its boundaries.

Figures: 93; 7; 1; 051 — 11; 651 — 32; 200 (³; 20; 36; 4 by 7; 76 — 11.

Columns of figures and multiplications: 1; 76; 186; 20 — 0; 10; 1; 110; 99 — 086; 9; 186; 186 — 18; 100; 1; 7000; 2,100,000; 300; 1130; 6,300,000; 2,100,000; 2,100,000 — giving 273,000,000; then 3 .16; 2; 5 10; 2; 9 6; 6; 14.