Similar Parts

Besides the animal spirits, man consists of:

• spiritual air-aether, homogeneous with our animal spirit, and
• watery humor, homogeneous with the solid parts that can be compared to the earth-aether

The mixture of the animal spirits and humor forms the vital spirit, which is comparable to fire.

From the imperfect mixture of humor and earthly parts, blood is produced.

The more imperfect and contumacious parts’ mixture is yellow bile.

The perfect, but in which the most subtle humor evaporates, is black bile, acidic.

Satisfactorily perfect, but in which humor abounds, is urine.

[602] Satisfactorily perfect, but in which the extremes of tenuity and solidity are lacking, is slow pituita and mucus. Perfectly formed, flesh, nerves, and bones, as in it, more or less, according to the solid parts.

Nails and hair are of the same material as bones. But they do not harden in the same way.

• This is because the moist parts evaporate too quickly.

Teeth and horns, on the other hand, are made of the same material as bones and harden in a similar way.

• This is because they are covered with more moisture and coalesce more slowly.

Through the ears, the excrementitious spirit exhales, causing sibili and tinnitus, when that spirit is impeded by the filth of the ears and is then emitted with a hissing sound.

Through the eyes, the spirit also exhales, as can be seen in menstruating women, whose eyes are said to emit vapor.

The entire body of a menstruating woman is filled with humors which are emitted through the monthly flow. Their eyes are purified through the lacrimal ducts.

Fear and coldness spread throughout the body when the fluid parts converge into a single focal point, where the greatest heat is produced.

Thus, after eating, the extremities become cold because the hot parts converge into the stomach.

In the case of fever, which begins with cold, there is a certain focal point where the humor first ignites, either in the heart, as I believe, or elsewhere.

This vitious humor first infects the blood, which, as it enters the heart, produces fever.

Hence, we can know the onset of fever from this.

There are 3 focal points in man:

1. The heart

This is made from air and blood

2. The brain

This is also made from air and blood, but more attenuated.

3. The ventricle

This is made from food and the substance of the ventricle itself.

In the heart, the substance is like a fire made from dry matter and dense substance.

In the brain, the substance is like a fire made from wine spirit.

In the ventricle, the substance is like a fire made from green wood.

In this way, food can also spontaneously putrefy and become hot without the addition of any external heat, just like hay, etc.

There is heat in the liver, which is kindled by the mixture of bile and blood that is already present in it.

The liver is hot when it contains a lot of blood that has already been formed.

However, it quickly draws in chyle, or the parts that contain the most heat, which are found in food. This is how the remaining parts are more easily corrupted. Hence, it is believed that the ventricle is cold.

Other unnatural fires are kindled throughout the body: phlegmones, erysipelas, abscesses, and the like.

For example, there is anastomosis between veins and arteries, through which phlegm, that is, blood that is warmer and more acrid, permeates the vein’s tunic.

Or the same blood, although it cannot penetrate through the vein’s tunic, spreads to the extremities together with scattered spirits, causing erysipelas.

Or some material that is beyond nature accumulates in a particular place, where it putrefies on its own, as in a simple abscess. Or this putrefaction communicates with the veins and arteries because of their proximity, as in pleurisy.

In wounds, fire is also kindled, which opens up the veins and arteries, and the blood’s fæces are corrupted there.