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So likewise they may overturn houses, that are slightly built; but for solid buildings, they overturn them not; unless attended with earthquakes. Sometimes also, they sweep down whole magazines of snow from the mountains, and almost bury the vallies with it; an accident that befel Solyman in the Sultanian plains. Sometimes likewise they cause great inundations of water.

The winds sometimes blow whole rivers out of their channels, and leave their bottoms bare; for if a strong wind should, after a great drought, continue blowing several days, in the direction of the current, so as by tearing down the water, to drive it into the sea, and keep the sea-water from coming in, the river must necessarily become dry in many places.

ADMONITIONS,

When the poles are changed, the observations also, as to north and south, must change: for as the absence and presence of the sun is here the cause; this varies according as the north or south pole is elevated. But it may be an invariable thing, that there is more sea towards the south, and more land towards the north; which also contributes much to the difference of the winds.

Winds are generated a thousand ways, as we shall see presently; whence it is not easy to fix observations in a thing of so much uncertainty; but such as we lay down, will doubtless generally hold good.

SECT. VII.

THE HISTORY OF THE LOCAL ORIGINS OF WINDS; IN PROSECUTION OF THE SEVENTH ARTICLE OF THE TABLE OF ENQUIRY.

TRANSITION.

It is a difficult enquiry, to settle the local origin of the winds; since whence they come, and whither they go, is, even in scripture, remarked for a secret thing. And this we speak not as to the fountains of particular winds (of which hereafter;) but of the wombs of the winds in general. Some derive them from on high; some search for them in the deep; but there are few who seek them in the middle; where they are most frequently generated. And this is the manner of men, to pass over what lies before their feet, and look out for obscurities. Thus much is certain, that winds are either natives, or strangers, and as it were traders in vapours; importing

them collected intoclouds, and exporting themagain to and from different countries; whence winds are produced as by traffick and exchange. But our present enquiry is about native winds; for those which are foreign in some parts, are natives in others. There are then three local origins hereof; viz. 1. as they breathe out, or spring from the earth; 2. as they are thrown down from on high; and 3. as they are made up here in the body of the air. Those thrown down from above, are generated two ways; being, either precipitated before they are formed into clouds; or afterwards, when the clouds are rarified and dispersed. We now proceed to their history.

The poets fable, that the kingdom of Eolus was seated in dens and caverns under the earth; where the winds were imprisoned, and some-, times let out.

Certain philosophical divines dwell upon these. words of scripture: "Who brings forth the winds out of his treasures." As if the winds proceeded from certain subterraneal repositories, or magazines. But nothing can be built upon this; for the scripture likewise speaks of the "Treasures of snow and hail;" which, no one doubts, are generated above.

There is, doubtless, a large quantity of air contained in the bowels of the earth; and this

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probably may gradually breathe from thence; and sometimes upon particular causes rush out in a body.

An indirect phenomenon.

In great droughts and the midst of summer, when the earth cracks, large quantities of water are frequently observed to burst out in dry and sandy places: and if water, which is a gross body, sometimes does this; it is probable, that the subtile and rarified body of air may do it oftener.

When air breathes out of the earth gradually and in small parcels, it is little perceived, at first; but when many of these small eruptions come together, they make a wind; as a river is formed of springs. And this seems to be the case; because the ancients have observed, that many winds at their first rise, and in the places whence they rise, first blow weak; but afterwards grow stronger, in their progress; exactly after the manner of rivers.

There are some places found in the sea, and also some lakes, which swell very considerably, though no winds are there found to blow; whence this should seem owing to some subterraneous blasts.

A great quantity or force of subterraneous spirit or vapour, is necessary to shake or cleave the earth; but a less will serve to raise the water:

and therefore earthquakes seldom happen; but swellings and risings of the waters frequently.

It is likewise a common observation, that ters swell and rise a little before storms.

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The weak subterraneous spirit or vapour, that escapes in small parcels, is not perceived upon the earth till it gathers into a wind; because of the porosity of the earth: but when it gets out from under the waters, it is presently perceived, from the swelling of the waters, by reason of their continuity.

We before observed*, that hollow and cavernous countries have their waiting or serving winds; insomuch that those winds may truly seem to have their local origins from the earth.

On large rocky mountains, the winds are found to blow both sooner, that is, before they are perceived in the vallies; and more frequent, that is, whilst the vallies enjoy a calin: but all mountains and rocks are cavernous.

In Denbighshire, in Wales, which is a mountainous and rocky country, there are said to be such strong eruptions of winds from certain caverns, as to toss back any kind of apparel thrown into them, a great height into the air.

There are certain holes, in a rocky cliff at Aber Barry, near the Severn, in Wales, whereto

* Sect. V.

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