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There are, besides these, other ancient names of winds; as Apeliotes, Argestes, Olympias, Sciron, Hellespontius, Iapyx, &c. but we pay little regard to them; it is sufficient to have given fixed appellatious to the several winds in the regular order and division of the horizon: for we lay no stress upon the understanding of authors; as authors contain but very little to our purpose.



THERE is no point of the heavens, but a wind may blow from it; so that if the heavens were divided into as many points as there are degrees in the horizon, there will, one time or other, be found winds blowing from each.*

There are some whole countries where it never rains, or at most very seldom; but none where the winds do not blow; and that frequently.

There are few phænomena observed of general

That is, supposing, for example, the horizon divided into 360 degrees; as all circles are by mathematicians.

winds; and no wonder, as these winds are principally found within the tropics, where chiefly lie the places, condemned by the ancients for un inhabitable. But those who sail in the open sea, between the tropics, observe a wind, or breeze, continually blowing from east to west; which is not so gentle, but that partly by its own motion, and partly by affecting the current of the sea, it renders it impossible for ships to return towards Peru, the same way they came.

In our European seas, there is observed (when the heavens are clear and serene, and no particular winds stirring) a certain gentle breeze, breathing from the east, and following the sun.

It is found by common observation, that the higher clouds generally move from east to west; and this even at the same time when there is calm, or a wind blowing in a contrary direction, near the surface of the earth. And if this prove not always the case, the reason may be owing to particular winds, sometimes blowing above; so as to disturb, or over-power this general wind.


If there be any such general wind, proceeding from the order of the motion of the heavens, it is not strong enough to resist the particular winds. And such a wind becomes more mani

fest within the tropics, by reason of the larger circles it there has to move in; and also high

up, for the same reason; and to enjoy the freer course. Therefore, whoever would endeavour to discover this wind without the tropics, and near the earth's surface (where it breathes but small and soft) let him make the experiment in the open and free air, in the greatest calms, and highest places; and that with a very moveable body; and towards the evening; because at this time the particular east wind blows less.


Let a careful observation be made of the weather cock, vanes, streamers, and the like, on the tops of steeples, high edifices, ships, &c. in order to determine whether, in the greatest calms, they do not always tend to the west.


It is matter of observation, that the east wind in Europe is a sharp and drying wind; but the west wind, on the contrary, moist and favourable. Does not this proceed from hence, that, upon a supposition of the air's motion from east to west, the east wind, which goes also in that direction, necessarily rarifies, and drives the air before it, so as to make it more dry and preda

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tory; whereas the west wind, which moves in a contrary direction, condenses, and turns the air back upon itself; from whence it becomes less sharp or cutting, and afterwards moistening?

Consult the enquiry of the motion of the tides,* to discover whether the waters move from east to west for if the heavens, and the waters, which are the extremities of the air, have this motion; it is highly probable that the air itself, which lies between them, participates of it likewise.


The two preceding phænomena we call indirect; as not pointing out the thing immediately, but consequentially: and this is a kind of phœnomena which we willingly admit and receive; in defect of a sufficient stock of direct ones.

It is a certain fact, that there blows a constant, manifest breeze between the tropics; but the cause thereof is doubtful. It may be owing to this; that the air, as we before observed, moves in the direction of the heavens; but less perceptibly without the tropics, because of the smaller circles there. Another reason may be this; that all air is expanded by heat; and, by this

* See the Novum Organum, Part II.

expansion, the contiguous air is of necessity impelled, so as to create that constant breeze; whilst the sun holds on its course: but this expansion must be more considerable within the tropics, where the sun is hottest; and again, but small without them, where it is colder. It might seem a crucial instance* for solving this difficulty, were it but known, whether this breeze continues by night, or not; because the rotation of the air continues by night, though the heat of the sun does not.

mine the point;

Now it is certain this breeze comes not in the night; but in the morning, or some time after the sun is up. Yet this instance does not deterbecause the nocturnal condenespecially in such places where the day and night are as different in heat and coldness, as they are equal in their lengths, may check and confound this natural but gentle motion.t

sation of the air,

If the air participate of the motion of the heavens; it follows, not only that the east wind coincides with, whilst the west wind opposes, the motion of the air; but also, that the north wind blows, as it were from above; and the south wind as from below, in our hemisphere;

*See Novum Organum, Part II. Aph. XXXVI. + See the appendix to Dr. Jurin's edition of Varenius,

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