BnF. Bibliothèque de l'Arsenal. Ms-8536

Swamps

The further you descend into low-lying valleys in places with marshes and swamps, the more you will find the air dense and heavy. Their inhabitants experience poor health, for dense vapors from deep chasms^{1We are reading "alto" here as the Latinate "deep" rather than "high".} cannot dissipate—just as in the lowlands where humidity accumulates because the dry winds aren't strong enough.

Rain

When the sun rises and enters these valleys, its heat gets trapped, so [the air] swelters, generating great corruption where marshy lands are found. [The miasma] rises through the air as dense fog and comes down again as heavy rain. It produces brutish beasts and filthy vermin, and the corrupt air makes people sick.

Mountains

In the mountains, as the sun appears, the day shines brightly and purges all the mist. The winds that blow all around drain and desiccate every humor. Because the air becomes pure and very refined moisture and heat no longer have any strength. Because of this, corruption cannot occur and people remain healthy.

Snow

[In the mountains] there is no substance by which air can be made heavier or set alight, and thus it is cold.^{*Really not clear about this: what is this "accendere" process that happens to air? >>Ask Winston.} Because it is hot in low-lying areas, moist air rises high up, and it reaches the cold; before it can go any higher it turns into snow and falls on the plains. In the mountains, because it is cold, [the snow] lasts, and in the valleys, it turns into water again.

Hail and Thunder

But when the sun gets warmer in the summer, the heat brings the moisture higher. It encounters colder zones, where it solidifies and turns into ice; then it falls noisily because it breaks and shatters into hailstones. But when the air is dry, it flashes as it strikes and splits the air in great thunder and lightning.

Wind

The pure air in that [colder] region resists and rejects change. And when these exhalations^{*Bad air rising from the valleys} arrive there it pushes them back down as if it had been attacked. The [pure] air gathers great power from this, so it moves strongly—and that is the wind that torments the sea and the land.

The Ocean

The great sea sits upon the round earth; it covers and bathes the greater part of it, and the land that stands above the waves emerges from it like a mountain. That which surrounds the land is called Ocean.^{1For medieval people this was the name of the single Ocean.} Through the strait of the Spanish Sea,^{2The Strait of Gibraltar.} Ocean pours [water] between the lands^{3Referring to the Mediterranean's placement in between the continents of Europe, Africa, and Asia.} into a sea called the Mediterranean.

The Ebb and Flow of the Sea, that is, the Tide

Every like attracts like and the moon rules over the humors. Thus, when she extends over the great sea, once per night and once per day the water of the sea rises towards her and leaves a great path uncovered along the shores of the ocean. Then the moon passes and the water that was low rises and returns.

The Horizon

Imagine you are on a high mountain looking all around in every direction: the sky will appear to you like the arch of a bridge, set upon the earth like [the mouth of] an oven. The circle around the edge is the horizon. Now, note that where it is midday, that hemisphere will be illuminated and it will be night on the other side.

Day and Night

If the globe of earth were like water, air, and fire—which are thin and do not block out the light— it would never be night in any place. But the sun cannot pass through the hard bones [of the earth] and thus the day fades little by little: the earth takes the day away from us and it gets dark due to the shadow cast upon us by its solid body.

Hours and Time

From here we calculate the measurement and the hours^{1this means passage of time} of all the time of the present world because the sun turns and every twenty-four hours it always sets in the west. In different places and at different times, the sun is always rising somewhere. Twenty-four hours is a natural day which is always the same, divided between day and night.

Spring

Once springtime begins, full of flowers and new shoots, it makes every shore temperate with gentle winds, moving the waves of the sea. At this time, the day from morning to evening is as long as the night which hides the sun from us; then until mid-June the day grows longer and the night recedes.

Spring begins in the middle of the month of March, when the sun enters into Aries. It has a moist and hot complexion^{1This comes from the theories of the humors} that makes everything fruitful. Living things are rekindled by love, ready for procreation and offspring [>>>e fete]^{2our manuscript lacks "e fete"} Moisture is taken from the past winter, and heat is drawn from the re-emerging sun.^{3"Nel ventre tuo si raccese l’amore, / per lo cui caldo ne l’etterna pace / così è germinato questo fiore" (Par. 33, ln. 7-9; prayer to Mary)}

Summer

In summer, the sun is closer than at any other time because its orbit gets nearer to us. It ripens fruit with its rays, and consumes [winter's] moisture. You will see twice as much daytime as nighttime. Then the amount begins to diminish little by little until the middle of September. This time is fiery by nature.

Autumn

Because the night and the day are equal, it begins to get cold and the heat draws down. And the days get shorter as the nights get longer, continuing until the middle of December. This time is called autumn, in which the contrasting heat and cold make the air gusty and bring heavy rains so that the dryness is removed by water.^{4Other witnesses read "secho"}.