T

CHA P. III.

Of the Clouds and Rain.

HE Clouds and Rain (a) we fhall find to be

no lefs 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 raifed 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_small 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 Atmosphere, 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 those 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 elfe into Showers of fmal! Rain, faHing in numerous, thick, fmall Drops: But if those Vapours are not only copious, but alfo 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 Regifter of the Weather for thirty Years, which his learned Grandfon, Dr. Samuel Clarke, put into my Hands, he, (I fay) faith, he scarce ever obferved the Rule to fail in all that Time; only he adds, If the Wind be in fome of the Eafterly 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 conden fing drives the Vapours into Clouds or Drops, then is way made for the Sun-beams, till the fame Vapours, being by further Condensation 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 small Drops of Rain, Hail, or Snow, now and then falling, before any Alteration hath been in the Weather S which I take to be from the Cold meeting fome of the ftraggling Vapours, or the uppermost of them, and condenfing them into Drops, before it arrives unto, and exerts itfelf 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, becaufe it gives Light to many other Phenomena 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 so 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 intense enough to freeze them: But if the Cold freezeth them in the Clouds, or in their Fall thro' 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 also their Rife to Vapours; but fuch Vapours as are de

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tached

Pfalmift faith, Pfal. lxv. 12, 13.) The little Hills rejoice on every fide, and the Valleys fhout for foy, they "alfo fing.

And

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

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Another Phenomenon refolvable from what hath been faid is, why a cold is always a vet 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 Solftice, 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 Frost; 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 wettest Months. And not only with us at Upminster, but in other Places, particularly at Zurich in Switzerland, they seem to have had as unfeasonable Cold and Wet as we. Fuit bic menfis præter modum humidus, & magno quidem vegetabilibus bominibufque damno. Multum computruit Fænum, &c. complains the Industrious and Learned Dr. J. J. Scheuchzer: Of which, and other Particulars, I have given a larger Account in Phil. Tranf. N° 321.

In which Tranfaction I have observed farther, that about the Equinoxes we (at Upminster at leaft) have oftentimes more Rain than at other Seafons. The Reafon of which is manifeft from what hath been faid, 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 Au tumn, 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 Seafons, when either the Vapours are fewer, or the Cold that is to condense 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 mutt needs fall down. Also many of those thicken'd

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

thicken'd Veficula run into one, and fo form Drops, greater or smaller, according to the Quantity of Vapours collected together.

As to the Rain of different Places, I have in some 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 Townly in Lancashire, 42 Inches and a half; at Upminster in Effex 19 Inches and a quarter; at Zurich in Switzerland 32 Inches and a quarter; at Pifa in Italy 43 Inches and a quarter; at Paris in France 19 Inches; and at Lifle 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 Caufest Of which, for the Reader's Satisfaction, I will give an Inftance 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. Peiresc (then in the Neighbourhood) ftrictly inquiring 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 to come from them; and because these Drops were laid, Non fupra ædificia, non in devexis lapidum fuperficiebus, uti debuerat contingere, fi è cælo fanguine pluiffet; fed in fubcavis potius & in foraminibus. Acceffit, quòd parietes iis tingebantur, non qui in mediis oppidis, fed qui agrorum vicini erant, neque fecundum partes elatiores, fed ad mediocrem folum alti tudinem, quantam volitare Papiliones folent. Gaffend. in vit Peiresk, 1. 2. p. 156..

So Dr. Merret faith alfo, Pluvia Sanguinis quàm certiffime confat effe tantum Infectorum excrementa; Pluvia Tritici quàm nihil aliud effe quàm Hedera bacciferæ grana à Sturnis devorata excretaque comparanti liquidiffimè patet. Pinax rerum, &c. p. 220.

The curious Worm tells of the raining of Brimstone, An. 1646. Maii 16. Hie Hafnia cùm ingenti pluviá tota urbs, omnefque ita inundarentur plateæ, ut greffus hominum impediret, Sulphureoque odore aërem inficeret, dilapfis aliquantulum aquis, quibufdam in locis colligere licuit Sulphureum pulverem, cujus portionem ferve, colore, odore, & aliis verum Sulphur ferentem. Muf. Worm. L. 1. C. 11. Seß. 1,

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Toge

Rains, as fome of the most eminent modern Philo

fophers

Together with the Rain we might take notice of other Meteors, particularly Snow; which altho' an irk fome Guest, yet hath its great Ufes, if all be true that the famous T. Bartholin faith of it, who wrote a Book de Nivis Ufu Medico. In which he fhews of what great Ufe Snow is in fructifying the Earth, preferving from the Plague, curing Fevers, Cholicks, Head-Aches, Tooth-Aches, Sore Eyes, Plurifies, (for which Ufe, he faith, his Country Women of Denmark keep Snow water gathered in March), alfo in prolonging Life, (of which he inftanceth in the Alpine Inhabitants, that live to a great Age,) and preferving dead Bodies; Inftances of which he gives in Perfons buried under the Snow in paffing the Alps, which are found uncorrupted in the Summer, when the Snow is melted; which fad Spectacle he himfelf was an EyeWitness of. And at Spitzberg in Greenland, dead Bodies remain entire and uncorrupted for thirty Years. And lastly, concerning fuch as are fo preferved when flain, he faith they remain in the fame Pofture and Figure: Of which he gives this odd Example. Vifum id extra urbem noftram [Hafniam] quum, 11 Feb. 1659. oppugnantes hoftes repellerentur, magnâque Arage occumberent; alii enim rigidi iratum vultum oftendebant, alii oculos elatos; alii ore diducto ringentes, alii brachiis extenfis Gladium minari, alii alio fitu proftrati jacebant. Barthol. de ufu Niv. c. 12.

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But altho' Snow be attended with the Effects here named, and others fpecified by the learned Bartholin; yet this is not to be attributed to any peculiar Virtue in the Show, but fome other Caufe. Thus when it is faid to fructify the Earth, it doth fo by guarding the Corn or other Vegetables against the intenfer Cold of the Air, especially the cold piercing Winds; which the Hufbandmen obferve to be the most injurious to their Corn of all Weathers. So for Conferving dead Bodies, it doth it by conftipating fuch Bodies, and preventing all fuch Fermentations or internal Conflicts of their Particles, as would produce Corruption.

Such an Example as the preceding is faid to have happened fome Years ago at Paris, in digging in a Cellar for fuppofed hidden Treasure; in which, after digging fome Hours, the Maid going to call her Mafter, found them all in their digging Poftures, but dead. This being noised abroad, brought in not only the People, but Magiftrates alfo, who found them accordingly; Ille qui ligone terram effoderat, & focius qui palâ effoffam terram removerat, ambo pedibus ftabant, quafi fuo quifque operi affixus incubuiffet; uxor unius' quafi ab opere defeffa in Scamno,

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