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SEQUELA CHARTARUM ;
SIVE INQUISITIO LEGITIMA
DE CALORE ET FRIGORE.
Charta suggestionis, sive memoria fira.
The sun-beams hot to sense.
to have a quality of cold, for that the greatest colds are noted to be about the full, and the greatest heats about the change. Query.
The beams of the stars have no sensible heat by themselves; but are conceived to have an augmentative heat of the sun-beams by the instance following. The same climate arctic and antarctic are observed to differ in cold, viz. that the antarctic is the more cold, and it is manifest the antarctic hemisphere is thinner planted with stars.
The heats observed to be greater in July than in June ; at which time the sun is nearest the greatest fixed stars, viz. Cor Leonis, Cauda Leonis, Spica, Virginis, Sirius, Canicula.
The conjunction of any two of the three highest planets noted to cause great heats.
Comets conceived by some to be as well causes as effects of heat, much more the stars.
The sun-beams have greater heat when they are more perpendicular than when they are more oblique: as appeareth in difference of regions, and the difference of the times of summer and winter in the same region; and chiefly in the difference of the hours of mid-day, mornings, evenings in the same day.
The heats more extreme in July and August than in May or June, commonly imputed to the stay and continuance of heat.
The heats more extreme under the tropics than under the line : commonly imputed to the stay and continuance of heat, because the sun there doth as it were double a cape.
The heats more about three or four of clock than at noon; commonly imputed to the stay and conti. nuance of heat.
The sun noted to be hotter when it shineth forth between clouds, than when the sky is open and serene.
The middle region of the air hath manifest effects of cold, notwithstanding locally it be nearer the sun, commonly imputed to antiperistasis, assuming that the beams of the sun are hot either by approach or by reflexion, and that falleth in the middle term between both; or if, as some conceive, it be only by reflexion, then the cold of that region resteth chiefly upon distance. The instances shewing the cold of that region, are the snows which descend, the hails
which descend, and the snows and extreme colds which are upon high mountains.
But Qu. of such mountains as adjoin to sandy vales, and not to fruitful vales, which minister no vapours; or of mountains above the region of vapours, as is reported of Olympus, where any inscription upon
the ashes of the altar remained untouched of wind or dew. And note, it is also reported, that men carry up sponges with vinegar to thicken their breath, the air growing too fine for respiration, which seemeth not to stand with coldness. The clouds make a mitigation of the heat of the
So doth the interposition of any body, which we term shades ; but yet the nights in summer are many times as hot to the feeling of men's bodies as the days are within doors, where the beams of the sun actually beat not.
There is no other nature of heat known from the celestial bodies or from the air, but that which cometh by the sun-beams. For in the countries near the pole, we see the extreme colds end in the summer months, as in the voyage of Nova Zembla, where they could not disengage their barks from the ice, no not in July, and met with great mountains of ice, some floating, some fixed, at that time of the year, being the heart of summer.
The caves under the earth noted to be warmer in winter than in summer, and so the waters that spring from within the earth.
Great quantity of sulphur, and sometimes naturally burning after the manner of Ætna, in Iceland; the like written of Groenland, and divers other the cold countries.*
The trees in the cold countries are such as are fuller of rosin, pitch, tar, which are matters apt for fire, and the woods themselves more combustible than those in much hotter countries; as, for example, fir, pineapple, juniper: Qu. whether their trees of the same kind that ours are, as oak and ash, bear not, in the more cold countries, a wood more brittle and ready to take fire than the same kinds with us ?
The sun-beams heat manifestly by reflexion, as in countries pent in with hills, upon walls or buildings, upon pavements, upon gravel more than earth, upon arable more than grass, upon rivers if they be not very open, &c.
The uniting or collection of the sun-beams multiplieth heat, as in burning-glasses, which are made thinner in the middle than on the sides, as I take it, contrary to spectacles; and the operation of them is, as I remember, first to place them between the sun and the body to be fired, and then to draw them upward towards the sun, which it is true maketh the angle of the cone sharper. But then I take it if the glass had been first placed at the same distance to which it is after drawn, it would not have had that force, and yet that had been all one to the sharpness of the angle. Qu.
* No doubt but infinite power the heat of the sun in cold countries, though it be not to the analogy of men, and fruits, &c.
So in that the sun's beams are hotter perpendicularly than obliquely, it may be imputed to the union of the beams, which in case of perpendicularity reflect into the very same lines with the direct; and the further from perpendicularity the more obtuse the angle, and the greater distance between the direct beam and the reflected beam.
The sun-beams raise vapours out of the earth, and when they withdraw they fall back in dews.
The sun-beams do many times scatter the mists which are in the mornings.
The sun-beams cause the divers returns of the herbs, plants, and fruits of the earth; for we see in lemon-trees and the like, that there is coming on at once fruit ripe, fruit unripe, and blossoms; which may shew that the plant worketh to put forth continually, were it not for the variations of the accesses and recesses of the sun, which call forth, and
The excessive heat of the sun doth wither and destroy vegetables, as well as the cold doth nip and blast them.
The heat or beams of the sun doth take away the smell of flowers, specially such as are of a milder odour.
The beams of the sun do disclose summer flowers, as the pimpernel, marigold, and almost all flowers else, for they close commonly morning and evening, or in over-cast weather, and open in the brightness of the sun : which is but imputed to dryness and moisture, which doth make the beams heavy or erect,