Fire Produced from Objects

How is Fire Ignited by Violent Motion Alone?

[4.087]

Violent motion is often found in lightning and whirlwinds. These happen when high clouds fall into lower ones. This explodes the intercepted air, as I explained in Meteoris.

The earth-aether particles in the physical clouds do not yet adhere to the fire-aether in this motion. But if they are rapidly agitated by any other cause, they immediately shake loose from each other. The air-aether globules around them then start to float in it. Thus, they will sustain their motion.

Therefore, any highly accelerated motion is sufficient to ignite fire in the clouds.

Even if they were previously motionless, once the earth-aether only float in the fire-aether, they acquire the most rapid agitation.

This is the same principle why a ship, not tethered by any ropes, cannot remain stationary in a rushing stream.

How is Fire Produced by the Mixture of Various Bodies?

[4.088] This violent motion almost never alone causes fire.

It is almost always mixed with air exhalations which easily transform either into flame or, at least, light, as seen in:

• will-o’-the-wisps around the Earth
• lightning in clouds
• shooting and falling stars in the high air.

Exhalations consist of the tiniest particles, divided into many branches. These wrap around denser particles derived from pungent juices or volatile salts.

These branches are usually so minute and closely-packed that nothing can pass through their interstices except the fire-aether.

However, the particles enveloped by these branches often form other larger intervals that the air-aether globules tend to fill.

At that point, the exhalation does not ignite. But sometimes, these spaces are occupied by particles of another exhalation or spirit.

When these expel the former along with the air-aether, they immediately leave their place, and, with their motion, generate fire.

Fire In Lightning and Shooting Stars

[4.089] In lightning or shooting stars, the cause that compiles multiple exhalations simultaneously becomes apparent due to the descent of one cloud into another.

However, in tranquil air, when one exhalation, densified and at rest due to cold, is easily penetrated by another coming from a warmer place or consisting of particles more suitable for motion or even impelled by a gentle wind, it rushes into its pores.

As a result, it expels particles into the air-aether.

Since the particles of the first exhalation are not yet so tightly connected that they cannot be separated by the impact of the others, they burst into flame.

I believe this is how shooting stars are ignited.

Fire in Those that Shine but Do Not Burn: Falling Stars

[4.090] When, however, the particles of an exhalation have coalesced into a substance so dense and viscous that they do not separate much, they emit only some light.

This is similar to that seen in:

• rotting wood
• fish preserved in salt
• drops of sea water, and the like.

The only reason for the light is that the air-aether globules are pushed away by the fire-aether.

The intervals between many joined terrestrial particles are so narrow that only the fire-aether can fit.

Even if this fire-aether does not have enough power to separate them, it easily has enough to drive the surrounding air-aether globules away.

I think falling stars are such particles.

Their material is often viscous and tenacious, as seen in those that have fallen to the ground.

Although it is not certain that this viscous material had light, there could have been some faint flame adhering to it.

Fire in Drops of Sea Water, Rotting Wood, and the Like.

[4.091]

When the flexible particles of these drops, mutually entangled, remain together, the rigid and smooth ones, due to the force of a storm or any other motion, are ejected from the drop.

These rigid particles vibrate like little spicules. They easily expel air-aether globules from their vicinity, thus producing light.

In rotting wood, fish that are beginning to dry, and similar substances, I think light arises solely because, while they are glowing, many passages are so narrow that they admit only the fire-aether.