Two Treatises on the Nature of the Elements and the Fifth Essence

ON THE ELEMENTS.
25

...nature, water is converted into air, from which there emerges a certain perpetual commotion, expanding itself everywhere, surrounding the whole face of the earth, and moistening it. Moreover, water having been made subtle (subtilis) in this manner, when, penetrating through the somewhat warm air, it reaches the colder and thicker [air], it is again compressed, condensed, diminished, and returns to its ancient disposition (ingenium), that is, the nature of water, rushing downwards drop by drop: a fall which tranquility necessarily follows, just as we experience in the time of rains: unless perhaps that vapor (vapor) and that continuous ascent of water should further persist with a greater abundance and force than the cold air can condense. Just as heat (calor) renders both the air and water subtler, rarer, and larger: so cold (frigus), the opposite of heat, renders the same things thicker, denser, and smaller: by this law drawing back again the winds (venti), which had vanished by the power of heat. This we shall perceive with our eyes and hands, if, with the mouth of an empty retort (Cornuta) placed in cold water, you place its belly over a fire; you will see immediately, as soon as it has first been heated [...]

b
con- [vinc]