* Let us suppose that the air has 4 of levity, being under water, and 8 if it is under the simple earth. Therefore the water has 4 of gravity between the air and the earth, and the earth has 8.

* The weight of the 4 elements is not given within the elements themselves. Fire 2 of gravity, air 4, water 8 and earth 16. And these weights were imagined to be given outside the heaviness of the elements, that is, above the sphere of fire.

And if the 3 elements are given in the sphere of fire, we shall say the air weighs 2, being in the medium which by itself weighed 4, and the water 6 and the earth 14, because the 2 with which the fire resists takes two of weight from the 3 elements.

And if the two other elements are weighed in the air, which in itself resists by 4, then the water, which was 8, weighs as 4, and the earth, which is 16, weighs as 12, and a thing heavier than the earth... And if any element is weighed in the water, which resists as 8, then the 16 of the earth weighs as 8.

Every element resists as much as is its weight, plus that which is sustained above it. Here one must add the levity of the fifth essence [quintessence].

In the penetrating of the elements into the elements from below upward, all those that enter are called heavy [bodies] entering into the light; and if such a mixture is made from above downward, that which penetrates is called light.

But if the light [element] of fire, which is 2, is drawn into the air, which is 4, that fire by itself will not remain in that air unless 6 of water be added to it; of which 6, two are lost against the 2 of the levity of the fire, and 4 remain, with which the water stays of weight equal to the air.

And if the air, which here is 4 of levity, enters into the eight of gravity of the water, then the 4 of levity of the air destroys 4 of the eight of the gravity of the water. Therefore there remain 4 of gravity equal to the 4 of gravity of the water. And if the earth were liquid like mercury, the 8 degrees of levity of the water consume the 8/16 of the gravity of the earth. There remain 8 equal to the 8 of the water.

Of liquids.
That body shows itself heavier which is in a lighter body; and that shows itself lighter which is in a heavier liquid.

This sheet must be coated with candle-smoke tempered with sweet glue, and then thinly smear the leaf with white-lead in oil, as is done for letters in print, and then print it in the common way. And thus such a leaf will appear shaded in the hollows and lit on the reliefs. Which here happens the contrary.

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