The works of the Honourable Robert Boyle, Esq., epitomiz'd by Richard Boulton ... ; illustrated with copper plates.

TITLE XVIII. Experiments and Observations touching the Coldness and Temperature of the Air.

* 1.11. THO' Gassendus and several others as∣sert, That the Air is Indifferent as to Cold and Heat; yet since Cold is only a Re∣lative Quality, and since the Parts of the Air, are of themselves in a less degree of Agitation, than the Humors about our Sensory; I see no reason why it should not be esteemed Cold: For notwithstanding it may acquire a conside∣rable degree of Heat by the adventitious Effects of the Sun-Beams, or fire; yet we see, that it naturally tends to coolness it self again. And as for the Coldness of the Air, tho' I deny not but that frigorifick Atoms may be mixed with it; yet I judge them not absolutely or al∣together requisite to the Production of Cold; since a bare Diminution of the motion of it's Parts, is sufficient to produce such a Quality in higher or more remiss degrees.

2. But the Principal intent of this Section being to produce Experiments and Observations;

I shall begin with the former. A sealed Weather-Glass with Spirit of Wine in it, being en∣closed in a Cylindrical Receiver, when the Air in the Receiver was exhausted, it subsided the length of a Barly-corn; but rose again when the Air was let in again; which Effects I attributed to the Expansion of the Included Air, when the External was drawn out. When the Air was drawn out of the Receiver, hot Bodies Exter∣nally applyed, affected not the Weather-Glass; but when the Air was let in again they caused the Spirit to rise sensibly.

3. To measure the Condensation of the Air by Cold, we made the following Experiments. And, First we enclosed Air in Weather-glasses hermetically sealed; which, when it was artifi∣cially or naturally refrigerated, and the Apex of the Weather-glass broke open, we could not discern, by the Water it received, that it was condensed above a 30th Part of it's former di∣mensions. A Glass-egg being inverted into Salt Water, in a Cold Night, the Air was so far condensed in it, That the Water rose five Inches in the Stem. And Jan. 29 the Air ex∣tended into 2057 Spaces was in a frosty Night contracted to 1965 Spaces. So that the great∣est degree of Condensation we could observe was a 22 Part and a little above a third. But a Mixture of Snow and Salt being applied to the Elliptical Part of the Glass, the Water rose 4 Inches higher than in the former Experiment; and the Air was contracted from 1965 Spaces to 1860; so that the Artificial Cold contracted is more in respect of the Contraction, which the natural Cold produced, than That Condensation

was in Proportion to it's natural temper or ra∣ther a moderate degree of Coldness.

4. But to proceed to Observations: Cold may hinder the Operation of the Sun upon the Air in the middle of Summer; and I am told, That it hath been observed to Snow in Green∣land all Mid-summer Night, and in the North∣ern Parts of Muscovy it hath been observed, That severe Frosts happened in the close of Au∣gust. And further, Capt. Weymouth says, That in the midst of Summer, when they sailed not near the Latitude of Nova Zembla, their ve∣ry sails and Tackling were froze: To which we shall add, that the English when they were sailing to Cherry-Island, which lyes betwixt 74 and 75 degrees Latitude; in July it froze so hard, that the Ice hung upon their Cloaths.

5. As for the degrees of Cold in the Air, Dr. Fletcher tells us, that in Russia, if they go out of a warm Room into the Cold, it makes them Breath with difficulty. It is observ'd at Moscow, That Water thrown up into the Air falls down congealed, the Air is so Cold; and at Smolensko in Russia, the Spittle freezes before it can fall from one's Mouth to the Ground.

6. I have observ'd the Air grows sensibly heavier, in frosty Weather; but whether it depends on any frigorifick Atoms dispersed through the Air, or not, I shall leave to be de∣cided by further Tryals. In Northern Countries it is observ'd, That foggy Weather presently vanishes when Frost begins; the moist Vapours being, by that, condensed and precipitated, and the Surface of the Earth so closed up, that other Vapours were repressed, and kept from rising;

and the Air hath been by several observ'd to have been much more clear in the Winter, here in England, and Sweedland, and elsewhere, than at other times.

7. The Refraction of Luminaries in the Nor∣thern Air in Nova Zembla is so great, that the Dutch-Men observ'd the Sun to appear to them 14 Days sooner than it ought to have done. And Capt. James tells us, That he observ'd the Lati∣tude of Charlton-Island to vary 52 Minutes, and the Sun to rise 20 Minutes sooner than it ought to rise: Besides several Instances of Refraction, laid down in the History of the Air.

8. To what we have said, of the Coldness of the Air; we shall subjoyn the Relations and Observations of Navigators, which we shall either propose as promiscuous, or in Con∣firmation of the three following Observati∣ons.

1. That the greater or lesser Coldness of the Air in several Climates and Countries, is nothing near so regularly proportionate to their Respective distances, from the Pole or their Vicinity to the E∣quator as Men are wont to presume. It hath been observ'd, That of Places of an equal distance from the Northern and Southern Poles, those near the latter are Colder. Tho' in Moscow, the Cold is almost intolerable; yet in Edenburgh, which is a degree more Northwards, the Air is temperate enough, and the Snow seldom lies on the Ground. Mr. Pool in his Northern Voyage tells us, That it did not freeze near so hard near the 79th degree as in the 73d. And tho' Nova Zembla, lies near 4, 5 and 6 de∣grees more Southerly from the Pole than Green∣land,

yet the latter hath Grass and Trees and such Beasts as feed upon them; whereas in No∣va Zembla there is no Grass and only such Beasts as feed on Flesh. To which I shall add, That Josephus Acosta tells us, That under the Line, when the Sun was in the Zenith and just entred into Aries, in March, he felt himself ve∣ry Cold; and he likewise tells us, That under the Burning Zone in Quitto and the Plains of Peru the Air is temperate; at Potofi very Cold; and in Aethiopia, Brasile and the Moluccoes ve∣ry Hot. And he observes further, That Snow lyes on the tops of the Hills, and that it is ex∣tremely Cold, when the Sun is for their Zenith under the Line. Mr. Hudson in his Voyage hath observed, That one Day, they were much disturbed with Ice; and that the next Day, it was very Hot: And we are further in∣formed by Acosta, That tho' the Seas of Mo∣zambigus and Ormus in the East, and Panama in the West, are very Hot; yet that of Peru of the same height is very Cold. And Capt. James's Observes, That tho' Charlton-Island is Cold∣er than Nova Zembla, yet is it of the same La∣titude with Cambridge. To which I shall sub∣joyn, That an English Navigator tells us, That tho' Pustozera in Russia is 68 ½ degrees, yet it is well inhabited, and a Town of great Trade. And in Hudson's Voyage it was observed, that beyond 80 degrees they found it moderately warm.

2. The next Observation is, That the degree both of Heat and Cold in the Air may be much greater in the same Climate, and the same Place,

at several seasons of the year, or even at several times of the same Day, than most Men would believe.

In Proof of this Proposition we shall produce the following Testimonies of Travellers and of Navigators. And 1. That there is a great variety Weather in Russia, Dr. Fletcher witnesses, who observes, that tho' all Winter the Ground is covered with Snow and the Fields frozen up; yet the Fields in the Summer are covered with flowers and filled with the delightful noise of Birds; and then the Weather is as much too Hot, as it was before Cold; June, July and August being warmer than the Summer in Eng∣land: And the like is confirmed by the Obser∣vations of others, amongst whom Olearius tells us, that at Moscow he saw Melons of 40 Pound weight better than those in Italy.

And at Pequin, the Royal City of China, tho' it is but 42 degrees Latitude; yet in the Win∣ter, Martinius the Jesuit tells, us it is a hard frost for four Months together, so that all the Rivers are froze up. And Prosper Alpinus tells us, that Grand Cairo, which is only 6 degrees from the Tropick of Cancer, tho' the Summers are insupportably Hot; yet the Winters are considerably Cold: And one thing he there takes notice of is, That in that Place they are seldom or never troubled with Distillations or Rheums. And Purchase tells us, That in Green∣land one Day will be extremely Cold and the next as violent Hot; so that at Mid-night Tobac∣co may be lighted at the Sun-beams, by the help of a Glass: To which Relations I shall add, That Capt. James tells us, That in Charlton-Island,

tho' the Winter was excessive Cold; yet in June it was so Hot, with Thunder and Light∣ning, That the Men were forced to go a shore to cool themselves in the Water.

Alpinus tells us likewise, that in Aegypt the Air is some part of the Day extremely Hot and at other times very temperate and cool. And O∣learius tells us, That travelling over Mount Tau∣rus in Persia; tho' it was too Hot in the Day for them to proceed in their Journey; yet at Night they were so benummed with the Cold, That they were scarce able to light off their Horses; and the same Traveller observ'd at Fallu in Per∣sia both Lightning and Thunder, Winds, Snow, Rain and Ice, in one Night. And in Charlton-Island tho' the Heat of the Sun in June be insup∣portable in the Day; yet at Night, the Cold is strong enough to freeze Water, in Vessels, an Inch thick.

3. The third Observation is, That in many Places the Temperature of the Air, as to Cold and Heat, seems not to depend so much on the Eleva∣tion of the Pole, as upon the Nature and Circum∣stances of the Winds that Blow there.

It is commonly known, That in this Part of the World, Northerly and North-easterly Winds are accompained with Cold, and in Winter with Frost: But I once observ'd here in England a South-Wind when it froze hard; and Capt. James in his Voyage hath observ'd the like: And Prosper Alpinus observes in Ae∣gypt, That the North-Winds are extraordina∣ry cooling; and that upon the Blowing of the Aetesian Winds the Plague ceases, at Grand Cairo.

That this cooling Quality depends on the changes it receives from the Places it passes over, is highly probable, as well as that it ac∣quires other Qualities the like way. Acosta Lib. 3. Cap. 9. Takes notice of Winds, That, in some Parts of the Indies, so corrode Iron-gates, That they will crumble away in one's Fingers. And the same Author tells us, That tho' in Spain an Easterly-wind is Hot and troubles one; yet in Murria, it is Cold and healthful; but in Carthagena not far from the former Place, it is troublesome and unhealth∣ful. The Meridional (which they of the Ocean call South, and those of the Mediterranean Sea, Mezzo Giorno) is commonly Rainy and Boyste∣rous; and in the same City, I speak of, it is wholesome and pleasant. And in Peru, he says, the South and South-west-winds are very plea∣sing.

How the Winds come by these Qualities I shall not now dispute; but to give some light into the matter I shall propose the following Experiment.

Setting a Weather-Glass with a flat Basis up∣on a Board, and Blowing several times upon it with a large pair of Bellows, tho' the Air seem∣ed Cold to my Hand; yet the Pendulous drop ascended a little, the Air being a little heated in the Bellows: But if the Clack of the Bellows was so fastned, That the Air must wholly en∣ter in at the Nose of it; the stream of Air, which was by that means drawn toward the Weather-Glass from the Window, being cooler, would cause the Bubble to subside.

But having provided such a Tile as they lay on the ridges of Houses and filled the hollow side with a Mixture of Snow and Salt, and Part of that Mixture being placed about the Bellows; I found, That the Air blown upon my Hand was, by that means, highly refrigerated: And this Air be∣ing blown upon the Ball of a common Weather-Glass, the Water manifestly ascended; but subsided again, when we left off blowing. But to prosecute the Tryal, we drew back the Nose of the Bellows, and upon that, the Wind blowing along that Cavity upon the Weather-Glass, manifested a higher degree of Cold∣ness.

But tho' it from hence appears, That frigori∣fick Atoms may refrigerate the Air; yet I be∣lieve not, that all Winds must necessarily be cooled so; since the Cold Air near the Poles swimming upon that which fills the lower Part of the Atmosphere, may, for want of a Reflecti∣on of the Sun-Beams, be so Cold, as to cool the Air suddenly, when by the falling of Rain it is beat down upon us: For Acosta hath observ'd, upon Mountains higher than the Alps, That the Air was extremely Cold. And the Hollan∣ders who failed within 17 degrees of the Pole observ'd, That their Cold Winds were chiefly Northerly and North-easterly. But,

To conclude this Title, I shall add an in∣stance or two to shew, That Cold Winds re∣ceive not so much their Qualities from the Quarters from whence they Blow, as from the Regions over which they pass. For Mr. Wood tells us, That tho' in England the most troublesome and unwholesome Winds

came from the Sea; yet in New-England those are the most wholesome: Because the North-east-wind coming from the Sea thaws the Ice and melts the Snow; but the North-west-wind coming over the Land causes Cold. And Capt. James observ'd the like in Charlton-Island, viz. That the South-wind was Coldest which came over a frozen Tract of Land.

Particulars referrable to the XVIII Title.

• 1. The little sealed Weather-Glass being immersed in Water, contained in a Glass-Vial greased in the inside, when the Water was froze, and the Ball of the Weather-Glass was incrustated, being taken out, the Ice was broke off: Upon which the Tinged Liquor immedi∣ately rose in the shank of the Weather-Glass; but presently subsided again below the former Mark; from whence it appears, That the Air may communicate a greater degree of Cold than Ice it self.
• 2. Having placed a Weather-Glass, made by the Standard at Gresham-College, in a Cel∣lar, where Beer continued unfroze in a very sharp Winter; last Night and this Morning the Tinged Liquor stood 2 Divisions and ⅛ above the freezing Mark; but being removed into the Garden, it subsided to the freezing Mark: But tho' the Cellar was warmer than the Air; yet it was not so warm as my Chamber; the Weather-Glass there standing two Inches above the freezing Mark, in the Morning before the fire was made; and in the Summer the Tinged

• Spirit ascended to the 8th 9th and sometimes almost to the tenth Mark.
• 3. The last Night being rendered very Cold by Snow, Frost and Wind; this Morning, the Weather-Glass being removed into the Garden, the Tinged Spirit subsided two Divisions be∣low the freezing Mark: Yet the Cellar did not become so much Hotter, by an 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉; but that Oyl of Aniseeds continued undissolv'd in it till, the next Morning, tho' the mode∣rate warmth of Spring or Autumn is sufficient to keep it fluid.
• 4. A Weather-Glass being held in the Stream of Water as it came reaking Hot out of the Pump, the Liquor subsided considerably; and being carried to my Chamber, the Air there being Colder than the Water, it was depressed lower.
• 5. Having held a Weather-Glass in the reaking stream of Pump-Water, the Spirit rose about 5 Inches higher than it did at a Well in Oxford; and being in some measure immersed in a Spring that usually smoaks in the Winter, it was raised a little higher. And the Weather-Glass being placed on the North side of the House about Noon, I found that the temper of the Air then, was much the same with the temper of the smoaking Spring.
• 6. Feb. 19. The Frost having continued 3 Days, the Spirit was raised as high, by the warmth of the Spring as it used to be. The next Day the Spring beginning to smoak, the warmth of the Water raised the Spirit near a quarter of an Inch higher than it used to rise at the

• Spring-head some Months ago. And the Water was then much warmer than the Air, for the Spirit when brought to my Chamber subsided; the Ground without being covered with a lit∣tle Snow
• 7. A Gentleman told me, That he had ob∣serv'd the Tinged Spirit sometimes higher, when it was frosty, than when it was not. And he further told me, That the Weather-Glass being left in Water till it was froze, when it was cleared of the Ice and exposed to the Air, the Spirit manifesty subsided. The size of the Ball of this Weather-Glass was as big as that of a large Crab, and the Stem was a∣bout 2 foot and ½ long. And the distance be∣twixt the station which the Spirit rested at in the Water and the Air was above three Inches.

A Relation given me by an Ingenious Gentleman lately returned out of Poland.

1. In frosty clear Weather, he observ'd the Sun and two Parhelions one Eastward and the other Westward; betwixt ten and twelve a Clock; and when the Sun-shine appeared it was full of glit∣tering Particles of Ice.

2. A Dutch and a Scotch Ship having sailed beyond Greenland, within one degree of the Pole, they observed, That tho' there were vast Regions of Ice near the shores; yet near the Pole, the Sea was open and free enough. From the North-East they observ'd, That there came a great rolling Sea, not unlike the Spanish Seas: And that the Cold was no violenter than that in Greenland. And further they observ'd,

That sailing from Greenland, the Compass first varied a Point and then two, and when they came near the Pole, the Compass varied 4 Points, and that towards the East.

The Captain likewise told me, That they are troubled at Sea, sometimes with thick Fogs, some of which last half a Day, others a Day; and others a whole Day.

And he likewise told me, That lying at An∣chor near Bellsound on the coast of Greenland, near a very high Rock, he and some others got to the top of it; which they judged to be half a Mile high: And when they came there; they found the Weather clear and the Sky serene, and so Hot that they were forced to strip them∣selves: But below they could discern a thick fogg; which when they came down, they found was very Cold, and Dark.

A Passage taken out of the Czars-Doctor's Letter.

• 1. At Vologda in the North-East from Mos∣cow we found the Cold Weather in December not to last 3 Days; but the Rain was unusual and dangerous. And for 30 years past the Win∣ters have been so moderate, That People are not froze on the Roads in several Postures; but sometimes they lose their Noses, and have their Faces froze.
• 2. The Warmer the Room is in the Day, the thicker the Hoar is at Night upon the Glass; being sometimes an Inch thick: And if it be a small Frost, The Nails of the Windows and Doors will be tipped with Frost. The Falconers say. That the Birds creep under the Snow at

• Nights. Bears make themselves Caves against Winter, and I remember I kept one two Days without meat or drink; he in the mean time, making a Lather with his Tongue and sucking his Paws.
• 3. A Wind from the Sea causes a Thaw as well as at Archangel. The Air is so healthful they use very little Physick, so that the Poor∣er sort live 80 or 100 years old.

Notes

• * 1.1

  Of the tem∣per of the Air.