The history of the Royal-Society of London for the improving of natural knowledge by Tho. Sprat.
Sprat, Thomas, 1635-1713., Cowley, Abraham, 1618-1667. To the Royal Society.
Page  [unnumbered]Page  173

A METHOD For making a History of the Wea∣ther. By Mr. HOOK.

FOr the better making a History of the Wea∣ther, I conceive it requisite to observe,
  • 1. The Strength and Quarter of the Winds, and to register the Changes as often as they hap∣pen; both which may be very conveniently shewn, by a small addition to an ordinary Wea∣ther-clock.
  • 2. The Degrees of Heat and Cold in the Air; which will be best observed by a sealed Thermo∣meter, graduated according to the Degrees of Expansion, which bear a known proportion to the whole bulk of Liquor, the beginning of which gra∣dation, should be that dimension which the Liquor hath, when encompassed with Water, just begin∣ning to freeze, and the degrees of Expansion, either greater or less, should be set or marked above it or below it.
  • 3. The Degrees of Dryness and Moisture in the Air; which may be most conveniently observed by a Hygroscope, made with the single beard of a wild Oat perfectly ripe, set upright and headed with an Index, after the way described by Emanuel Magnan; the conversions and degrees of which, may be mea∣sured by divisions made on the rim of a Circle, in Page  174 the Center of which, the Index is turned round: The beginning or Standard of which Degree of Rotation, should be that, to which the Index points, when the beard, being throughly wet, or covered with Water, is quite unwreathed, and becomes straight. But because of the smalness of this part of the Oat, the cod of a wild Vetch may be used instead of it, which will be a much larger Index, and will be altogether as sensible of the changes of the Air.
  • 4. The degrees of Pressure in the Air: which may be several wayes observed, but best of all with an Instrument with Quicksilver, contrived so, as either by means of water or an Index, it may sensibly exhibit the minute variations of that Acti∣on.
  • 5. The constitution and face of the Sky or Hea∣vens; and this is best done by the eye; here should be observed, whether the Sky be clear or clouded; and if clouded, after what manner; whether with high Exhalations or great white Clouds, or dark thick ones. Whether those Clouds afford Fogs or Mists, or Sleet, or Rain, or Snow, &c. Whether the under side of those Clouds be flat or waved and ir∣regular, as I have often seen before thunder. Which way they drive, whether all one way, or some one way, some another; and whether any of these be the same with the Wind that blows below; the Colour and face of the Sky at the rising and setting of the Sun and Moon; what Haloes or Rings may happen to encompass those Luminaries, their big∣ness form and number.
  • 6. What Effects are produc'd upon other bo∣dies: As what Aches and Distempers in the bodies of men: what Diseases are most rife, as Colds, Fe∣vours, Page  175 Agues, &c. What putrefactions or other changes are produc'd in other bodies; As the sweat∣ing of Marble, the burning blew of a Candle, the blasting of Trees and Corn; the unusual sprouting, growth, or decay of any Plants or Vegetables: the putrefaction of bodies not usual; the plenty or scarcity of Insects; of several Fruits, Grains, Flow∣ers, Roots, Cattel, Fishes, Birds, any thing notable of that kind. What conveniences or inconveniences may happen in the year, in any kind, as by flouds, droughts, violent showers, &c. What nights produce dews and hoar-frosts, and what not?
  • 7. What Thunders and Lightnings happen, and what Effects they produce; as souring Beer or Ale, turning Milk, killing Silk-worms, &c?
  • 8. Any thing extraordinary in the Tides; as double Tides, later or earlier, greater or less Tides than ordinary. Rising or drying of Springs; Co∣mets or unusual Apparitions, new Stars, Ignes fatui or shining Exhalations, or the like.

These should all or most of them be diligently observed and registred by some one, that is alwayes conversant in or neer the same place.

Now that these and some other, hereafter to be mentioned, may be registred so as to be most con∣venient for the making of comparisons, requisite for the raising Axioms, whereby the Cause or Laws of Weather may be found out; It will be desirable to order them so, that the Scheme of a whole Moneth, may at one view be presented to the Eye: And this may conveniently be done on the pages of a Book in folio, allowing fifteen dayes for one side, and fifteen for the other. Let each of those pages be divided into nine Columes, and distinguished by Page  176 perpendicular lines; let each of the first six Co∣lumes be half an inch wide, and the three last equal∣ly share the remaining of the side.

Let each Colume have the title of what it is to contain, in the first at least, written at the top of it: As, let the first Colume towards the left hand, con∣tain the dayes of the Moneth, or place of the Sun, and the remarkable hours of each day. The second, the Place, Latitude, Distance, Ages and Phaces of the Moon. The third the Quarters and strength of Winds. The fourth the Heat and Cold of the sea∣son. The fifth the Dryness and Moisture of it. The sixth the Degrees of pressure. The seventh the fa∣ces and appearances of the Sky. The eighth the Effects of the Weather upon other bodies, Thun∣ders, Lightnings, or any thing extraordinary. The ninth general Deductions, Corollaries or Syllo∣gisms, arising from the comparing the several Phae∣nomena together.

That the Columes may be large enough to con∣tain what they are designed for, it will be necessary, that the particulars be expressed with some Cha∣racters, as brief and compendious as is possible. The two first by the Figures and Characters of the Signs, commonly us'd in Almanacks. The Winds may be exprest by the Letters, by which they are ex∣prest in small Sea-Cards: and the degrees of strength by 1, 2, 3, 4, &c. according as they are marked in the contrivance of the Weather-cock. The degrees of Heat and Cold may be exprest by the Numbers appropriate to the Divisions of the Thermometer. The Dryness and Moisture, by the Divisions in the rim of the Hydroscope. The pressure by Figures denoting the height of the Mercurial Cylinder. But Page  177 for the faces of the Sky, they are so many, that ma∣ny of them want proper names; and therefore it will be convenient to agree upon some determi∣nate ones, by which the most usual may be in brief exprest. As let Cleer signifie a very cleer Sky with∣out any Clouds or Exhalations: Checker'd a cleer Sky, with many great white round Clouds, such as are very usual in Summer. Hazy, a Sky that looks whitish, by reason of the thickness of the higher parts of the Air, by some Exhalation not formed in∣to Clouds. Thick, a Sky more whitened by a grea∣ter company of Vapours: these do usually make the Luminaries look bearded or hairy, and are of∣tentimes the cause of the appearance of Rings and Haloes about the Sun as well as the Moon. Overcast, when the Vapours so whiten and thicken the Air, that the Sun cannot break through; and of this there are very many degrees, which may be exprest by a little, much, more, very much overcast, &c. Let Hairy signifie a Sky that hath many small, thin and high Exhalations, which resemble locks of hair, or flakes of Hemp or Flax: whose varieties may be exprest by straight or curv'd, &c. according to the resemblance they bear. Let Water'd signifie a Sky that has many high thin and small Clouds, looking almost like water'd Tabby, called in some places a Mackeril Sky. Let a Sky be called Waved, when those Clouds appear much bigger and lower, but much after the same manner. Cloudy, when the Sky has many thick dark Clouds. Lowring, when the Sky is not very much overcast, but hath also under∣neath many thick dark Clouds which threaten rain. The signification of gloomy, foggy, misty, sleet∣ing, driving, rainy, snowy, reaches or racks va∣riable, Page  178 &c. are well known, they being very com∣monly used. There may be also several faces of the Sky compounded of two or more of these, which may be intelligibly enough exprest by two or more of these names. It is likewise desirable, that the particulars of the eighth and ninth Columes may be entered in as little room, and as few words as are sufficient to signifie them intelligibly and plainly.

It were to be wisht that there were divers in se∣veral parts of the World, but especially in distant parts of this Kingdom, that would undertake this work, and that such would agree upon a common way somewhat after this manner, that as neer as could be, the same method and words might be made use of. The benefit of which way is easily e∣nough conceivable.

As for the Method of using and digesting those so collected Observations; That will be more ad∣vantageously considered when the Supellex is pro∣vided; A Workman being then best able to fit and prepare his Tools, for his work, when he sees what materials he has to work upon.