Why is the Sky and Sea Blue?

The whiteness or blackness of clouds come only from their exposure to the light of the stars, or to the shadow, both of themselves and of their neighbors.

There are only 2 things to note here.

1. The surfaces of transparent bodies reflect a part of the rays that come towards them.

This is why light can penetrate better through three pikes of water than it does through a little foam which is also water with several surfaces.

• The first surface reflects a part of this light
• The second surface reflects another part, and so on

In this way, there is almost none or no more that passes through.

This is why the following are not transparent:

• crushed glass
• snow
• thick clouds

2. The action of luminous bodies is only to push the fire-aether in a straight line to our eyes.

The ordinary movement of the small particles of this fire-aether in the air around us is to roll.

This is like a ball rolling on the ground, even though it has only been pushed in a straight line.

The “white” bodies are those that can make them roll in this way. Examples of these are all those that lack transparency because of the multitude of their surfaces:

• foam
• crushed glass
• snow
• clouds.

Why is the Sky and Sea Blue?

This is why the sky appears blue when very pure and free of all clouds.

The sky does not emit any light of its own.

It would appear extremely black if there were no exhalations or vapors at all above us.

They are always there to reflect some rays towards our eyes.

They push back towards us the small parts of the fire-aether that the sun or the other stars have pushed against them.

When these vapors are in sufficient number, the fire-aether being pushed back towards us by the first ones, meets others afterwards which make its small parts roll and whirl, before they reach us.

This then makes the sky appear white.

Whereas if it does not meet enough to make its parts whirl in this way, it would only appear blue, according to what has just been said about the nature of the blue color.

This same cause also makes the water of the sea seem to be blue where it is very pure and deep.

This is because:

• only a few rays are reflected from its surface
• none of those that penetrate it return.

Sunset and Sunrise

The sky towards the sun appears red when the sun sets or rises.

In those times, the light has to pass through:

• more clouds or fogs than during noon or daytime when the sky is blue
• less dark clouds as when the sky is gray

This light suffers refraction in these fogs.

It causes the fire-aether that transmit it to whirl in the same direction as a ball would that came from the same side rolling on the ground.

In this way, the whirling of the lowest ones is always increased by the action of those that are higher up, because it is supposed to be stronger than theirs.

This is enough to make the red color appear, which is reflected afterwards in the clouds which spread them on all sides in the sky.

This color appearing in the morning presages winds or rain. This is because it shows that there are few clouds towards the East. It means that the sun will be able to raise a lot of vapors before noon. This will cause fogs to rise.

In the evening, this color testifies to good weather because there are only few or no clouds towards the west. This means that:

• the Eastern winds must reign
• the fogs descend during the night.