Employ the varied dyeing of cloths by smearing them with tinted egg, that is, mixed with the yolk, and then wash it with water that dissolves the cooked egg, and mix with such egg the juice of a herb.

2 - b a - c - d - o - 1 m - 4 - (m)
Here d, with a power equal to the fourth part of the weight m, drags that weight, that is, with a power equal to one pound. And from c too that weight will be dragged, but with a power equal to the fourth part of the weight that remains in m, that is, there remaining in m 2 pounds because of the real appendage m c that lifts it upward with a power of two; therefore that appendage takes on a load of 2 pounds and 2 remain in m. Therefore with a power equal to the fourth part of that 2 of m, m will be moved against its friction with the plane that supports it, so that, adding half a pound of power above the 2 of c, that weight will be dragged from its place. And in demonstration it seems that here 2 and a half pounds are what drag it, but, as you have seen, it is nothing but half a pound, which becomes equal to the resistance of the 2 pounds that remain in m, while the other 2 pounds go toward the mover c.

a sustains the 4 pounds of m, b sustains 3 of them, c sustains 2, d sustains no part of them but handles one by friction, that is, with a power equal to the quarter of that weight m. Therefore a sustains it all but does not rub it, d sustains none of it but rubs it all, because in that d there is found neither lever nor counter-lever, and the same happens in a, where there is no lever and counter-lever, nor in any other line is that lever and counter-lever found.
The friction is always the quarter of that weight which is dragged, which weight becomes lighter the more it is dragged along a line closer to the line that falls upon it perpendicularly.

The more the weight of the body increases, the more the power of the friction diminishes.

The more the heaviness of the body dragged above the site of equality increases, the more the power of its friction diminishes.
And that weight will become heavier above that site of equality which is dragged by a cord of lesser obliquity.
And the power of the friction of the weight dragged above the site of equality increases as much as the obliquity of the cord that drags it increases.
Among equal weights, that one will show itself heavier which in equal time makes the greater movement, and that one will show itself lighter which in the same time makes less motion.

m - g 4 - n

f h (m) - 4 - p
The weight contends with the cord that suspends it as much as the power that with a similar cord would wish to move a similar weight in a similar obliquity of motion. It is proved. I say ...

4 2 1 - 4 a - n b
If the front of the beam a b weighs at a with a power of one, and that one is put into a power of 4 by means of the cord that pulls it along the obliquity a n, the weight of 4 pounds, which resists the descent of that front, finds nothing but one pound a of real weight, while the other is potential weight, which, as has been said, has in itself no heaviness, whence that weight of 4 lifts the foot.

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