Anti-friction wheels stacked to infinity; steel pivots
A column of ever-larger wheels, right-angled pivot ends, and contact at two points
The sheet develops Leonardo's low-friction pivot into a tower of wheels: a central column of discs, each larger than the one below, mounted so a shaft turns with ever less resistance. He calls this invention 'in the first degree of perfection' because ease of motion can be increased to infinity simply by adding more wheels underneath. Side notes weigh turning a wheel on its pivot against turning it together with its pivot, prescribe a pivot ended in right angles that touches its supports almost at a point (needing 7 wheels where another needed 11), and recommend that the wheels and pivot be made of tempered steel. A cross-armed bearing frame and a lattice support are drawn alongside.
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Each added wheel increases ease of motion without limit
This invention is in the first degree of perfection, that is, of ease, because it goes on to infinity: every wheel added below acquires degrees of ease of motion, and such addition can go on forever, so the ease of the motion can be increased infinitely. The tall column of discs of increasing size is the drawing of this idea.
Turning on the pivot versus turning with the pivot
Turning the wheel upon its pivot is of equal difficulty to turning it together with its pivot; the only difference is that the wheel turning on its pivot enlarges and ruins its hole and wears the pivot, whereas the wheel united with its pivot keeps its hole and wears only the pivot against its own support.
A right-angled pivot end: 7 wheels instead of 11
Because the outer edge of a thick pivot would need infinitely many wheels to roll truly, the remedy is a pivot whose end has right angles, touching its supports almost at a point. This design is better than the earlier one marked f: that one wanted 11 wheels while this needs only 7, works better, and can be stood upright.
Pivot touching two wheels; make everything of tempered steel
In another figure the pivot contacts two wheels at two points, keeping the motion at the widest angle attainable among acute angles, where a b is the motion of the two wheels and the circle the motion of the pivot. Leonardo adds that the whole may be corrected by the invention drawn on the reverse of this leaf, and that both the wheels and their pivot be of tempered steel.