Places; the one ferving to carry him into his Harbour, the other to bring him out. But I fhould go too far to take notice of all Particulars (f). Leaving therefore the Winds, I proceed in the next Place to the Clouds and Rain.

Comparison. In half an Hours Time after it has reached the Shore, it fans pretty briskly, and fo encreafeth gradually till twelve a Clock; then it is commonly strongest, and lasts fo till two or three, a very brisk Gale. After three it begins to die away again, and gradually withdraws its force till all is spent ; and about five a Clock· it is lulled afleep, and comes no more

till next Morning.

And as the Sea Breezes do blow in the Day, and rest in the Night; fo on the contrary [The Land-Breezes] blow in the Night, and reft in the Day, alternately fucceeding each other.

They fpring up between fix and twelve at Night, and last till fix, eight, or ten in the Morning. Dampier's Difc. of Winds, ch. 4.

(f) One Thing more I believe fome of my Friends will expect from me is, that I fhew the Refult of comparing my own Obfervations of the Winds, with others they know I have from Ireland, Switzerland, Italy, France, New-England, and fome of our Parts of England. But the Obfervations being fome of them but of one Year, and most of the rest of but a few Years, I have not been able to determine any great Matters. The chief of what I have obferved is, that the Winds in all thefe Places feldom agree, but when they moft certainly do fo, it is commonly when the Winds are ftrong, and of long continuance in the fame Quarter: And more I think in the Northerly and Eafterly, than other Points. Also a strong Wind in one Place, is oftentimes a weak one in another Place, or moderate, according as Places have been nearer or farther diftant. Vid. Phil. Tranf. No. 297, and 321. But to give a good and tolerable Account of this or any other of the Weather, it is neceffary to have good Hiftories thereof from all Parts; which, as yet we have but few of, and they imperfect, for want of longer and fufficient Obfervations.

T

CHA P. III.

Of the Clouds and Rain.

HE Clouds and Rain (a) we shall find to be no less useful Meteors than the last mentioned; as is manifeft in the refreshing pleasant Shades which the Clouds afford, and the fertile Dews and Showers which they pour down on the Trees and Plants,

(a) Clouds and Rain are made of Vapours raised from Water, or Moisture only. So that I utterly exclude the Notion of Dry, Terrene Exhalations, or Fumes, talked much of by moft Philofophers; Fumes being really no other than the humid Parts of Bodies refpectively Dry.

Thefe Vapours are demonftratively no other than fmall Bubbles, or Veficulæ detached from the Waters by the Power of the Solar, or Subterraneous Heat, or both. Of which fee Book 2. Chap. 5. Note (b). And being lighter than the Atmofphere, are buoyed up thereby, until they become of an equal Weight therewith, in fome of its Regions aloft in the Air, or nearer the Earth; in which thofe Vapours are formed into Clouds, Rain, Snow, Hail, Lightning, Dew, Mifts, and other Meteors.

In this Formation of Meteors the grand Agent is Cold, which commonly, if not always, occupies the fuperior Regions of the Air; as is manifeft from thofe Mountains which exalt their lofty Tops into the upper and middle Regions, and are always covered with Snow and Ice.

This Cold, if it approaches near the Earth, prefently precipitates the Vapours, either in Dews; or if the Vapours more copiously afcend, and foon meet the Cold, they are then condenfed into Mifling, or else into Showers of fmall Rain, falling in numerous, thick, fmall Drops: But if thofe Vapours are not only copious, but also as heavy as our lower Air it felf, (by means their Bladders are thick and fuller of Water,) in this Cafe they become vifible, fwim but a little Height above the Earth, and make what we call a Mift or Fog. But if they are a Degree lighter, fo as to mount higher, but not any great Height, as alfo meet not with Cold enough to condenfe them, nor Wind to diffipate them, they then form an heavy, thick, dark Sky, lafting oftentimes for feveral Weeks

without

Plants, which would languish and die with perpetual Drought, but are hereby made Verdant and Flourishing, Gay and Ornamental; fo that (as the Pfalmift

without either Sun or Rain. And in this Cafe, I have fcarce ever known it to Rain, till it hath been firft Fair, and then Foul. And Mr. Clarke, (an ingenious Clergyman of Norfolk, who in his Life-time, long before me, took notice of it, and kept a Register of the Weather for thirty Years, which his learned Grandfon, Dr. Samuel Clarke put into my Hands, he, I fay) faith, he fcarce ever obferved the Rule to fail in all that Time; only he adds, If the Wind be in fome of the easterly Points. But I have obferved the fame to happen, be the Wind where it will. And from what hath been faid, the Cafe is eafily accounted for, viz. whilft the Vapours remain in the fame State, the Weather doth fo too. And fuch Weather is generally attended with moderate Warmth, and with little or no Wind to difturb the Vapours, and an heavy Atmosphere to fupport them, the Barometer being commonly high then. But when the Cold approacheth, and by condenfing drives the Vapours into Clouds or Drops, then is way made for the Sun-beams, till the fame Vapours, being by further Condenfation formed into Rain, fall down in Drops.

The Cold's approaching the Vapours, and confequently the Alteration of fuch dark Weather I have beforehand perceived, by fome few imall Drops of Rain, Hail, or Snow, now and then falling, before any Alteration hath been in the Weather; which I take to be from the Cold meeting fome of the fraggling Vapours, or the uppermost of them, and condenfing them into Drops, before it arrives unto, and exerts it felf upon the main Body of Vapours below.

I have more largely than ordinary infifted upon this part of the Weather, partly, as being fomewhat out of the way; but chiefly, because it gives Light to many other Phanomena of the Weather. Particularly we may hence difcover the Original of Clouds, Rain, Hail and Snow; that they are Vapours carried aloft by the Gravity of the Air, which meeting together fo as to make a Fog above, they thereby form a Cloud. If the Cold condenfeth them into Drops, they then fall in Rain, if the Cold be not intenfe enough to freeze them: But if the Cold freezeth them in the Clouds, or in their Fall through the Air, they then become Hail or Snow.

As to Lightning, and other enkindled Vapours, I need fay little in this Place, and fhall therefore only obferve, that they owe alfo their Rife to Vapours; but fuch Vapours as are de

C 3

tached

Book I. Pfalmift faith, Pfal. lxv. 12, 13.) The little Hills rejoice on every fide, and the Valleys fhout for Joy, they allo fing.

And,

tached from mineral Juices, or at least that are mingled with them, and are fired by Fermentation.

Another Phanomenon refolvable from what hath been faid is, why cold, is always a wet Summer, viz. because the Vapours rifing plentifully then, are by the Cold foon collected into Rain. A remarkable Inftance of this we had in the Summer of 1708, part of which, efpecially about the Solstice, was much colder than ufually. On June 12, it was fo cold, that my Thermometer was near the Point of hoar Froft, and in fome Places I heard there was an hoar Froft; and during all the cool Weather of that Month, we had frequent and large Rains, fo that the whole Month's Rain amounted to above two Inches Depth, which is a large Quantity for Upminster, even in the wetteft Months. And not only with us at Upminfter, but in other Places, particularly at Zurich in Switzerland, they feem to have had as unfeafonable Cold and Wet as we. Fuit hic menfis- -prater modum humidus, & magno quidem vegetabilibus hominibufque damno. Multum computruit Fænum, &c. complains the induftrious and learned Dr. J. J. Scheuchzer: Of which, and other Particulars, I have given a larger Account in Phil. Tranf. No. 321.

In which Tranfaction I have obferved farther, that about the Equinoxes we (at Upminster at leaft) have oftentimes more Rain than at other Seasons. The Reason of which is manifest from what hath been said, viz. in Spring, when the Earth and Waters are loofed from the brumal Conftipations, the Vapours arife in great Plenty: And the like they do in Autumn, when the Summer Heats, that both diffipated them, and warmed the fuperior Regions, are abated; and then the Cold of the fuperior Regions meeting them, condenseth them into Showers, more plentifully than at other Seasons, when either the Vapours are fewer, or the Cold that is to condenfe them is lefs.

The manner how Vapours are precipitated by the Cold, or reduced into Drops, I conceive to be thus: Vapours being, as I faid, no other than inflated Veficula of Water; when they meet with a colder Air than what is contained in them, the contained Air is reduced into a lefs Space, and the watery Shell or Cafe rendered thicker by that means, so as to become heavier than the Air, by which they are buoyed up, and confequently muft needs fall down. Alfo many of those

thickned

And, if to these Uses, we fhould add the Origine of Fountains and Rivers, to Vapours and the Rains,

thickned Veficula run into one, and fo form Drops, greater or fmaller, according to the Quantity of Vapours collected together.

As to the Rain of different Places, I have in fome of our Tranfactions affigned the Quantities; particularly in the laft cited Tranfaction, I have affigned thefe, viz. the Depth of the Rain one Year with another, in English Measure, if it was to ftagnate on the Earth, would amount unto, at Townely in Lancashire, 42 Inches; at Upminster in Effex 19 Inches; at Zurich in Switzerland 32 Inches; at Pifa in Italy 43 Inches; at Paris in France 19 Inches; and at Life in Flanders 24 Inches. It would be endless to reckon up the bloody and other prodigious Rains taken notice of by Hiftorians, and other Authors, as præternatural and ominous Accidents; but, if ftrictly pried into, will be found owing to natural Causes: Of which, for the Reader's Satisfaction, I will give an Instance or two. A bloody Rain was imagined to have fallen in France, which put the Country People into fo great a Fright, that they left their Work in the Fields, and in great hafte flew to the Neighbouring Houses. Peirife (then in the Neighbourhood) Ariely enquiring into the Caufe, found it to be only red Drops coming from a fort of Butterfly that flew about in great Numbers at that Time, as he concluded from seeing fuch red Drops come from them; and because these Drops were laid, Non fupra adificia, non in devexis lapidum fuperficiebus, uti debuerat contingere, fi è cælo fanguine pluiffet; fed in fubcavis potius in foraminibus. Acceffit, quòd parietes iis tinge& bantur, non qui in mediis oppidis, fed qui agrorum vicini erant, neque fecundum partes elatiores, fed ad mediocrem folùm altitudinem, quantam volitare Papiliones folent. Gaffend in vit. Peiresk. L. 2. p. 156.

So Dr. Merret faith alfo, Pluvia Sanguinis quàm certiffimè conftat effe tantùm Infectorum excrementa: Pluvia Tritici quàm nihil aliud effe quàm Hedera baccifera grana à Sturnis devorata excretaque comparanti liquidissimè patet. Pinax rerum, &c. p. 220.

The curious Worm tells of the raining of Brimftone, An. 1646. Maii 16. Hic Hafnia cùm ingenti pluviâ tota urbs, omnefque ita inundarentur platea, ut greffus hominum impediret, Sulphureoque odore aërem inficeret, dilapfis aliquantulum aquis, quibufdam in locis colligere licuit Sulphureum pulverem, cujus portionem fervo, colore, odore, & aliis verum Sulphur ferentem. Muf. Worm. L. I. c. 11. Sect. I.