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which burneth like a coal, and diminisheth not; but only waxeth brighter and whiter.' That it should do so is not strange: for we see iron red hot burneth, and consumeth not; but the strangeness is, that it should continue any time so; for iron, as soon as it is out of the fire, deadeth straightways. Certainly it were a thing of great use and profit, if you could find out fuel that would burn hot, and yet last long: neither am I altogether incredulous but there may be such candles as they say are made of salamander's wool; being a kind of mineral, which whiteneth also in the burning, and consumeth not. The question is this; flame must be made of somewhat; and commonly it is made of some tangible body which hath weight: but it is not impossible perhaps that it should be made of spirit or vapour in a body, (which spirit or vapour hath no weight,) such as is the matter of ignis fatuus. But then you will say, that that vapour also can last but a short time: to that it may be answered, that by the help of oil, and wax, and other candle-stuff, the flame may continue, and the wick not burn.

Experiment solitary œconomical touching cheap fuel.

775. Sea-coal lasts longer than charcoal; and charcoal of roots, being coaled into great pieces, lasts longer than ordinary charcoal. Turf, and peat, and cow-sheards, are cheap fuels, and last long. Small-coal, or briar-coal poured upon charcoal, make them last longer. Sedge is a cheap fuel to brew or bake with the rather because it is good for nothing else. Trial would be made of some mixture of sea-coal with earth or chalk; for if that mixture be2, as the sea-coal men use it, privily to make the bulk of the coal greater, it is deceit; but if it be used purposely, and be made known, it is saving.

Experiment solitary touching the gathering of wind for freshness.

3

776. It is at this day in use in Gaza, to couch potsheards or vessels of earth in their walls, to gather the wind from the top, and to pass it down in spouts into rooms. It is a device for freshness in great heats: and it is said there are some rooms in Italy and Spain for freshness, and gathering the winds and air, in the heats of summer; but they be but pennings of the winds and enlarging them again, and making them reverberate

1 Sandys, p. 111. But for brighter we ought, on the authority of the passage in Sandys, to read lighter.

2 So in the original. Bacon probably wrote be used.-J. S. 8 Sandys, p. 116.

and go round in circles, rather than this device of spouts in-the wall.

Experiment solitary touching the trials of airs.

777. There would be used much diligence in the choice of some bodies and places, (as it were) for the tasting of air; to discover the wholesomeness or unwholesomeness, as well of seasons, as of the seats of dwellings. It is certain that there be some houses, wherein confitures and pies will gather mould more than in others. And I am persuaded that a piece of raw flesh or fish will sooner corrupt in some airs than in others. They be noble experiments that can make this discovery; for they serve for a natural divination of seasons, better than the astronomers can by their figures: and again, they teach men where to choose their dwelling for their better health.

Experiment solitary touching increasing of milk in milch-beasts.

778. There is a kind of stone about Bethlehem, which they grind to powder and put into water whereof cattle drink; which maketh them give more milk. Surely there would be some better trials made of mixtures of water in ponds for cattle, to make them more milch, or to fatten them, or to keep them from murrain. It may be chalk and nitre are of the best.

Experiment solitary touching sand of the nature of glass.

779. It is reported, that in the valley near the mountain Carmel in Judea there is a sand, which of all other hath most affinity with glass 2; insomuch as other minerals laid in it turn to a glassy substance, without the fire; and again, glass put into it turneth into the mother-sand. The thing is very strange, if it be true: and it is likeliest to be caused by some natural furnace, or heat in the earth: and yet they do not speak of any eruption of flames. It were good to try in glassworks, whether the crude materials of glass, mingled with glass already made, and remolten, do not facilitate the making of glass with less heat.

Experiment solitary touching the growth of coral.

780. In the sea, upon the south-west of Sicily, much coral is found. It is a submarine plant. It hath no leaves: it brancheth only when it is under water; it is soft, and green of

1 Sandys, p. 142.

2 Id. p. 159.

3 Id. p. 184.

colour; but being brought into the air, it becometh hard and shining red, as we see. It is said also to have a white berry; but we find it not brought over with coral. Belike it is cast away as nothing worth: inquire better of it, for the discovery of the nature of the plant.

Experiment solitary touching the gathering of manna.

781. The manna of Calabria is the best, and in most plenty.' They gather it from the leaf of the mulberry-tree; but not of such mulberry-trees as grow in the valleys. And manna falleth upon the leaves by night, as other dews do. It should seem that before those dews come upon trees in the valleys, they dissipate, and cannot hold out. It should seem also, the mulberry-leaf itself hath some coagulating virtue, which inspissateth the dew; for that it is not found upon other trees: and we see by the silk-worm, which feedeth upon that leaf, what a dainty smooth juice it hath; and the leaves also (especially of the black mulberry) are somewhat bristly, which may help to preserve the dew. Certainly it were not amiss to observe a little better the dews that fall upon trees, or herbs growing on mountains; for it may be many dews fall, that spend before they come to the valleys. And I suppose that he that would gather the best May-dew for medicine, should gather it from the hills.

Experiment solitary touching the correcting of wine.

2

782. It is said they have a manner to prepare their Greek wines, to keep them from fuming and inebriating, by adding some sulphur or alum: whereof the one is unctuous, and the other is astringent. And certain it is that those two natures do best repress fumes. This experiment would be transferred unto other wine and strong beer, by putting in some like substances while they work; which may make them both to fume less, and to inflame less.

Experiment solitary touching the materials of wild-fire. 783. It is conceived by some (not improbably) that the reason why wild-fires (whereof the principal ingredient is bitumen) do not quench with water, is, for that the first concretion of

1 Sandys, p. 195.

2 Id. p. 203. Sandys is speaking of the Greek wines made on the sides of Vesuvius. VOL. II.

Q Q

bitumen is a mixture of a fiery and watery substance: so is not sulphur. This appeareth, for that in the place near Puteoli, which they call the Court of Vulcan, you shall hear under the earth a horrible thundering of fire and water conflicting together; and there break forth also spouts of boiling water. Now that place yieldeth great quantities of bitumen; whereas Etna and Vesuvius, and the like, which consist upon sulphur, shoot forth smoke, and ashes, and pumice, but no water. It is reported also, that bitumen mingled with lime, and put under water, will make as it were an artificial rock; the substance becometh so hard.

Experiment solitary touching plaster growing as hard as

marble.

784. There is a cement compounded of flour, whites of eggs, and stone powdered, that becometh hard as marble: wherewith Piscina Mirabilis, near Cuma, is said to have the walls plastered. And it is certain and tried, that the powder of loadstone and flint, by the addition of whites of eggs and gumdragon, made into paste, will in a few days harden to the hardness of a stone.

Experiment solitary touching judgment of the cure in some ulcers and hurts.

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785. It hath been noted by the ancients that in full or impure bodies, ulcers or hurts in the legs are hard to cure; and in the head more easy. The cause is, for that ulcers or hurts in the legs require desiccation, which by the defluxion of humours to the lower parts is hindered: whereas hurts and ulcers in the head require it not; but contrariwise dryness maketh them more apt to consolidate. And in modern observation, the like difference hath been found between Frenchmen and Englishmen; whereof the one's constitution is more dry, and the other's more moist. And therefore a hurt of the head is harder to cure in a Frenchman, and of the leg in an Englishman.

Experiment solitary touching the healthfulness or unhealthfulness of the southern wind.

786. It hath been noted by the ancients that southern winds blowing much without rain, do cause a feverous disposition of the year; but with rain, not. The cause is, for

1 Sandys, p. 210.

2 Id. p. 231. 8 Arist. Prob. i. 18.

4 Id. ib. i. 23.

that southern winds do of themselves qualify the air to be apt to cause fevers; but when showers are joined, they do refrigerate in part, and check the sultry heat of the southern wind. Therefore this holdeth not in the sea coasts, because the vapour of the sea, without showers, doth refresh.

Experiment solitary touching wounds.

787. It hath been noted by the ancients, that wounds which are made with brass heal more easily than wounds made with iron. The cause is, for that brass hath in itself a sanative virtue; and so in the very instant helpeth somewhat: but iron is corrosive and not sanative. And therefore it were good, that the instruments which are used by chirurgeons about wounds were rather of brass than iron.

Experiment solitary touching mortification by cold.

788. In the cold countries, when men's noses and ears are mortified and (as it were) gangrened with cold, if they come to a fire they rot off presently. The cause is, for that the few spirits that remain in those parts are suddenly drawn forth, and so putrefaction is made complete. But snow put upon them helpeth for that it preserveth those spirits that remain, till they can revive; and besides, snow hath in it a secret warmth as the monk proved out of the text, qui dat nivem sicut lanam, gelu sicut cineres spargit2; whereby he did infer, that snow did warm like wool, and frost did fret like ashes. Warm water also doth good; because by little and little it openeth the pores, without any sudden working upon the spirits. This experiment may be transferred unto the cure of gangrenes, either coming of themselves, or induced by too much applying of opiates; wherein you must beware of dry heat, and resort to things that are refrigerant, with an inward warmth and virtue of cherishing.

Experiment solitary touching weight.

789. Weigh iron and aqua fortis severally; then dissolve the iron in the aqua fortis, and weigh the dissolution; and you shall find it to bear as good weight as the bodies did severally; notwithstanding a good deal of waste by a thick vapour that issueth during the working; which sheweth that the opening

1 Arist. Prob. i. 35.

2 Ps. cxlvii. 16.

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