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of winds returns after every four years, which seems not to be true, for revolutions are not so quick. This indeed hath been by some men's diligence observed, that greatest and most notable seasons (for heat, snow, frost, warm winters, and cold summers) for the most part return after the revolution of five-and-thirty years.
The Motion of the Winds.
To the twenty-second, twenty-third, twenty-fourth, twentyfifth, twenty-sixth, and twenty-seventh articles. Connexion.
Men talk as if the wind were some body of itself, and by its own force did drive and agitate the air. Also, when the wind changes its place, they talk as if it did transport itself into another place. This is the vulgar's opinion; yet the philosophers themselves apply no remedy thereunto, but they likewise stammer at it, and do not any way contradict and oppose these errors.
of the winds. Then, when they have found a current, where the air makes no resistance, (as water when it finds a falling way,) then, whatso ever semblable matter they find by the way, they take into their fellowship, and mix it with their currents even as rivers do. So that the winds blow always from that side where their nurseries are which feed them.
5. Where there are no notable nurseries in any certain place, the winds stray very much, and do easily change their current, as in the middle of the sea, and large spacious fields.
6. Where there are great nurseries of the winds in one place, but in the way of its progress it hath but small additions, there the winds blow strongly in their beginnings, and by little and little they allay; and contrariwise, where they find good store of matter to feed on by the way, they are weak in the beginning, but gather strength by the way.
7. There are movable nurseries for the winds, namely, in the clouds, which many times are carried far away from the nurseries of vapours of which those clouds were made, by winds blowing high; then the nursery of the wind begins to be in that place where the clouds do begin to be dissolved into wind.
8. But the whirling of winds does not happen, because the wind which blows at first transports itself, but because either that is allayed and spent, or brought into order by another wind; and all this business depends on the various placings of the nurseries of winds, and variety of times, when vapours issuing out of these nurseries are dissolved.
1. We must therefore inquire concerning the raising of the motion of the winds, and of the direction of it, having already inquired of the local beginnings; and of those winds which have their beginning of motion in their first impulsion, as in those which are cast down from above or blow out of the earth, the raising of their motion is manifest: others descend below their own beginnings; others ascend, and being resisted by the air, become voluminous, especially near the angles of their violence; but of those which are engendered everywhere in this inferior air, (which are the frequentest of all the winds,) the inquisition seems to be somewhat obscure, although it be a vulgar thing, as we have set down in the commentation under the eighth article. 9. If there be nurseries of winds on contrary 2. We found likewise an image or representa-parts, as one nursery on the south, another on the tion of this in that close tower which we spake of before; for we varied that trial three ways. The first was that which we spake of before; namely, a fire of clear burning coals. The second was a kettle of seething water, the fire being set away, and then the motion of the cross of feathers was more slow and dull. The third was with both fire and kettle; and then the agitation of the cross of feathers was very vehement, so that sometimes it would whirl up and down, as if it had been in a petty whirlwind, the water yielding store of vapours, and the fire which stood by it dissipating and dispersing them.
3. So that the chief cause of exciting motion in the winds is the overcharging of the air by a new addition of air engendered by vapours. Now we must see concerning the direction of the motion, and of the whirling, which is a change of the direction.
4. The nurseries and food of the winds doth govern their progressive motion; which nurseries and feedings are like unto the springs of rivers; namely, the places where there are great store of vapours, for there is the native country
north side, the strongest wind will prevail; neither will there be contrary winds, but the stronger wind will brow continually, though it be somewhat dulled and tamed by the weaker wind, as it is in rivers, when the flowing of the sea comes in; for the sea's motion prevails, and is the only one, but it is somewhat curbed by the motion of the river; and if it so happen that one of those contrary winds, namely, that which was the strongest, be allayed, then presently the contrary will blow, from that side where it blew before, but lay hidden under the force and power of the greater.
10. As for example, if the nursery be at the north-east, the north-east wind will blow; but it there be two nurseries of winds, namely, another in the north, those winds for some tract of way will blow severally, but after the angle of confluence where they come together they will blow to the north-east, or with some inclination, according as the other nursery shall prove stronger.
11. If there be a nursery of wind on the north side, which may be distant from some country twenty miles, and is the stronger; another on the
east side, which is distant some ten miles, and is weaker; yet the east wind will blow for some hours, and a while after (namely, when its journey is ended) the north wind.
12. If the northern wind blow, and some hill stands in the way of it on the west side, a little while after the north-east wind will blow, compounded by the original, and that which is beaten back again.
13. If there be a nursery of winds in the earth on the northern side, and the breath thereof be carried directly upward, and it find a cold cloud on the west side, which turns it off the contrary way, there will blow a north-east wind.
14. Monition. Nurseries of winds in sea and land are constant, so that the spring and beginning of them may be the better perceived; but the nurseries of winds in the clouds are movable, so that in one place there is matter furnished for the winds, and they are formed in another, which makes the direction of motion in winds to be more confused and uncertain.
Those things we have produced for example's sake, the like are after the like manner; and hitherto of the direction of the motion of winds: now we must see concerning the longitude, and, as it were, the itinerary or journey of the winds, though it may seem we have already inquired of this under the notion of the latitude of winds; for latitude may by unlearned men also be taken for longitude, if winds take up more space laterally than they go forward in longitude.
14. If it be true that Columbus could upon the coasts of Portugal judge of the continent of America by the constant winds from the west, truly, the winds can travel a long journey.
15. If it be true that the dissolution of snows about the frozen seas, and Scandia do excite and raise northerly winds in Italy and Greece, &c., in the dogdays, surely these are long journeys.
16. It hath not yet been observed how much sooner a storm does arrive, according to the way it comes, (as for example, if it be an eastern wind,) how much sooner it comes from the east, and how much later from the west. And so much concerning the motion of winds in their progression or going forward: now we must see concerning the undulation or swelling of winds.
17. The undulation or swelling of winds is done in a few moments, so that a wind will (though it be strong) rise and fall by turns, at the least a hundred times in an hour; whereby it appears that the violence of winds is unequal; for neither rivers, though swift, nor currents in the sea, though strong, do rise in waves, unless the blowing of wind oe joined thereunto, neither hath the swelling of winds any equality in itself; for like unto the pulse of one's hand, sometimes it beats, and sometimes it intermits.
fers from the swelling of waters into waves in this, that in waters, after the waves are risen on high, they of themselves, and their own accord, do again fall to the place of them; whence it comes that (whatsoever poets say when they aggravate tempests, namely, that the waves are raised up to heaven, and again sink down to hell) the descent of the waves do not precipitate much below the plane and superficies of the water. But in the swelling of the air, where the motion of gravity or weight is wanting, the air is thrust down and raised almost in an equal manner. And thus much of undulation. Now we must inquire of the motion of conflict or striving.
19. The conflicts of winds and compounded conflicts we have partly inquired already. It is plain that winds are ubiquitary, especially the Which is likewise manifest by mildest of them.
this, that there are few days and hours wherein some gales do not blow in free places, and that inconstantly and variously enough. For winds which do not proceed from greater nurseries are vagabond and voluble, as it were, playing one with the other, sometimes driving forward, and sometimes flying back.
20. It hath been seen sometimes at sea, that winds have come from contrary parts together, which was plainly to be perceived by the pertur bation of the water on both sides, and the calmness in the middle between them; but after those contrary winds have met, either there hath followed a general calm of the water everywhere, namely, when the winds have broken and quelled one another equally; or the perturbation of the water hath continued, namely, when the stronger wind hath prevailed.
21. It is certain that, in the mountains of Peru, it hath often chanced that the wind at one time hath blown on the tops of the hills one way, and in the valleys the clean contrary way.
22. It is likewise certain here with us, that the clouds are carried one way, when the wind near us hath blown the contrary way.
23. It is likewise certain, that sometimes the higher clouds will outfly the lower clouds, so that they will go diverse, yea, and contrary ways, as it were in contrary currents.
24. It is likewise certain, that sometimes in the higher part of the air winds have been neither dis tracted nor moved forward; when here below they have been driven forward with a mad kind of violence, for the space of half a mile.
25. And it is likewise certain, contrariwise, that here below the air hath been very still, when above the clouds have been carried with a fresh and merry gale; but that happen more seldom. An indirect experiment. Likewise in waves, sometimes the upper water
18 The undulation or swelling of the air dif- is swifter, sometimes the lower; and sometimes
there are (but that is seldom) several currents of water, of that which is upperinost, and that which lieth beneath.
26. Nor are Virgil's testimonies altogether to be rejected, he being not utterly unskilful in natural philosophy.
Together rush the east and south-east wind, Nor doth wave calling south-west зtay behind. And again:
I all the winds have seen their battles join.
We have considered of the motions of winds, in the nature of things: we must now consider their motions in human engines; and, first of all, in the sails of ships.
The Motion of Winds in the Sails of Ships. 1. In our greatest Britain ships (for we have chosen those for our pattern) there are four masts, and sometimes five, set up one behind the other, in a direct line drawn through the middle of the ship. Which masts we will name thus:
2. The mainmast, which stands in the middle of the ship; the foremast, the mizenmast, (which is sometimes double,) and the spritmast.
3. Each mast consists of several pieces, which may be lifted up, and fashioned with several knots and joints, or taken away; some have three of them, some only two.
4. The spritsail-mast from the lower joint lies bending over the sea, from that it stands upright; all the other masts stand upright.
5. Upon these masts hang ten sails, and when there be two mizenmasts, twelve; the mainmast and foremast have three tiers of sails, which we will call the mainsail, the topsail, and the maintopsail; the rest have but two, wanting the maintopsail.
6. The sails are stretched out across, near the top of every joint of the mast, by certain beams which we call yards, to which the upper parts of the sails are fastened, the lower parts are fastened with ropes at each corner; the mainsails to the sides of the ship, top and main-topsails to the yards which are next below them.
7. The yard of every mast hangs across, only the yards of the mizenmast hang sloping, one end up, and the other down; in the rest they hang straight across the masts, like unto the letter T.
8. The mainsails of the mainmast, foremast, and boarsprit, are of a quadrangular parallello-| gram form; the top and main-topsails somewhat sharp, and growing narrow at the top; but the top mizensails are sharp, the lower or mainsails triangular.
9. In a ship of eleven hundred tons, which was one hundred and twelve feet long in the keel, and forty in breadth in the hold; the mainsail of the mainmast was two-and-forty feet deep, and eighty-seven feet broad.
deep, and eighty-four feet broad at the bottoni, and forty-two at the top.
11. The main-topsail was seven-and-twenty feet deep, and two-and-forty broad at the bottom, and one-and-twenty at the top.
12. The foremast mainsail was forty feet and a half deep, and seventy-two feet broad.
13. The topsail was six-and-forty feet and a half deep, and sixty-nine feet broad at the bottom, and six-and-thirty at the top.
14. The main-topsail was four-and-twenty feet deep, six-and-thirty feet broad at the bottom, and eighteen feet at the top.
15. The mizen-mainsail was on the upper part of the yard one-and-fifty feet broad; in that part which was joined to the yard seventy-two feet; the rest ending in a sharp point.
16. The topsail was thirty feet deep, fifty. seven feet broad at the bottom, and thirty feet at the top.
17. If there be two mizenmasts, the hindermost sails are less than the foremast about the fifth part.
18. The mainsail of the boarsprit was eightand-twenty feet deep and a half, and sixty feet broad.
19. The topsail five-and-twenty feet and a half deep, and sixty feet broad at the bottom, and thirty at the top.
20. The proportions of masts and sails do vary, not only according to the bigness of ships, but also according to the several uses for which they are built: some for fighting, some for merchandise, some for swiftness, &c. But the proportion of the dimension of sails is no way proportioned to the number of tons whereof the ships consist, seeing a ship of five hundred tons, or thereabout, may bear almost as large a sail as the other we speak of, which was almost as big again. Whence it proceeds that lesser ships are far swifter and speedier than great ones, not only by reason of their lightness, but also by reason of the largeness of their sails, in respect of the body of the ship; for to continue that proportion in bigger ships would be too vast and impossible a thing.
21. Each sail being stretched out at the top, and only tied by the corners at the bottom, the wind must needs cause it to swell, especially about the bottom, where it is slacker.
22. The swelling is far greater in the lower sails than in the upper, because they are not only parallelograms, and the other more pointed at the top, but also because the extent of the yard doth so far exceed the breadth of the ship's sides to which they are fastened, that of necessity, because of the looseness, there must be a great receipt for the wind; so that in the great ship which we proposed for an example, the swelling of the sail in a direct wind may be nine or ten
10. The topsail of the same mast was fifty feet feet inward.
23. By the same reason it also happens that all sails which are swelled by the wind, do gather themselves into a kind of arch or bow, so that of necessity much wind must slip through; insomuch, that in such a ship as we made mention of, that arch may be as high as a man.
24. But in the triangular sail of the mizenmast there must of necessity be a lesser swelling than in the quadrangular; as well because that figure is less capable, as, also, because that in the quadrangular three sides are slack and loose, but in the triangular only two, so that the wind is more sparingly received.
25. The motion of the wind in sails, the nearer it comes to the beak of the ship, the stronger it is, and sets the ship more forward, partly because it is in a place where, because of the sharpness of the beak-head, the waves are easilier cut in sunder; but, chiefly, because the motion at the beak draws on the ship; the motion from the stern and back part of the ship doth but drive it.
26. The motion of the winds in the sails of the upper tier advances more than that in the lower tier, because a violent motion is most violent when it is farthest removed from resistance, as in the wings and sails of windmills; but there is danger of drowning or overturning the ship: wherefore those sails are made narrower at the top, that they should not take in too much wind, and are chiefly made use of when there is not much wind.
27. Sails being placed in a direct line, one behind the other, of necessity those sails which stand behind must steal the wind from the foremost when the wind blows foreright; wherefore, if they be all spread out at once, the force of the wind hath scarce any power but in the mainmast sails, with little help of the lower sails of the boarsprit.
28. The best and most convenient ordering of sails, in a direct wind, is to have the two lower sails of the foremast hoisted up, for there (as we said before) the motion is most effectual; let also the topsail of the mainmast be hoisted up, for there will be so much room left under it, that there may be wind sufficient for the foresails, without any notable stealing of the wind from them.
29. By reason of the hinder sails stealing of the wind away from the foresails, we sail swifter with a side wind than with a fore wind. For with a side wind all the sails may be made use of, for they turn their sides to one another, and so hinder nor rob not one another.
30. Likewise, when a side wind blows, the sails are stilier stretched out against the wind, which somewhat restrains the wind, and sends it that way as it should blow, whereby it gains some strength. But that wind is most advantageous which blows cornerly between a fore wind and a sile wind
31. The lower boarsprit-sail can hardly ever be unuseful, for it cannot be robbed from gathering the wind which way soever it doth blow, either about the ship sides, or under the rest of the sails.
32. There is considerable* in the motion of winds in ships, both the impulsion and direction of them. For that direction, which is made by the helm, doth not belong to the present inquisition, but only as it hath a connexion with the motion of the winds in the sails.
Connexion. As the motion of impulsion or driving forward is in force at the beak, so is the motion of direction in the poop; therefore, for that the lower mizenmast sail is of greatest concernment, for it is, as it were, an assistant to the helm.
33. Seeing the compass is divided into two-andthirty points, so that the semicircles of it are sixteen points, there may be a progressive sailing, (without any casting aboard, which is used when the wind is clean contrary,) though of the sixteen parts there be but six favourable, and the other ten contrary. But that kind of sailing depends much upon the lower sail of the mizeninast. For whilst the adverse parts of the wind, being more powerful and not to be opposed by the helm alone, would turn the other sails, and the ship itself, against its intended course, that sail being stiffly stretched, favouring the helm, and strengthening its motion, turns the beak into the way of its course.
34. All manner of wind in the sails doth somewhat burden and depress the ship, and so much the more when it blows most from above. So that in the greatest storms, first they lower their yards and take away the upper sails, and if need be, all the rest, cut down the masts, cast their goods into the sea, and their ordnance, &c., to lighten the ship and make it swim and give way to the waves.
35. By this motion of the winds in the sails of ships, (if it be a merry and prosperous gale,) a merchant's ship may sail sixscore Italian miles in four-and-twenty hours; for there are certain packet boats which are built a purpose for swiftness, (that are called caravels,) which will go further. But when the wind is clean contrary, they fly to this last refuge, and a very weak one, to go on their course, namely, to proceed sideway, as the wind will suffer them, out of their course, then turn their way again towards their course, and so proceed in an angular way. By which progression (which is less than creeping, for serpents creep on by crooked turnings, but they make angles) they may, in four-and-twenty hours, go fifteen miles' journey.
1. This motion of winds in sails of ships hath
i. e. to be considered.
three chief heads and fountains of its impulsion, or driving forward, from whence it flows and derives; whence also precepts may be taken to increase and strengthen it.
2. The first spring comes from the quantity of the wind which is received; for questionless more wind helps more than less; wherefore the quantity of wind must be carefully procured, which will be done if, like wise householders, we be good husbands, and take care nothing be stolen from us. Wherefore we must be very careful
that no wind may be lost.
3. The wind blows either above the ships or below them, to the very superficies and surface of the sea; and as provident men use to look most after the least things, (for the greater no man can choose but look after,) so we will first look after these lower winds, which questionless cannot perform so much as the higher.
4. As concerning the winds which blow chiefly about the sides of the ships, and under their sails, it is the office of the main boarsprit-sail, which lies low and sloping, to gather them into it, that | there may be no waste nor loss of wind; and this of itself does good, and hinders not the wind which fills the other sails. And about this I do not see what can be done more by the industry of man, unless they should perchance fix such low sails out of the middle of the ship, like wings or feathers, two on each side when the wind blows right.
5. But, concerning the bewaring of being robbed, which happens when the hinder sails (in a fore-right wind) steal the wind away from the foresails, (for in a side wind all the sails are set a-work,) I know not what can be added to the care man hath already taken to prevent it, unless when there is a fore wind, there may be made a kind of stairs, or scale of sails, that the hindermost sails of the mizzenmast may be the lowest, the middle ones at the mainmast a little higher, the foremast, at the foremast, highest of all, that one sail may not hinder but rather help the other, delivering and passing over the wind from one to another. And let so much be observed of the first fountain of impulsion.
6. The second fountain of impulsion consists in the manner of striking the sail with the wind, which, if through the contraction of the wind it be acute and swift, will move more; if obtuse and languishing, less.
7. As concerning this, it is of great moment, and much to the purpose, to let the sails have a reasonable extension and swelling; for if they be stretched out stiff, they will, like a wall, beat back the wind; if they be too loose, there will be a weak impulsion.
8. Touching this, human industry hath behaved itself well in some things, though it was more by chance than out of any good judgment. For, in a side wind, they gather up that part of the VOL. III.-58
sail as much as they can which is opposite against the wind: and by that means they set in the wind into that part where it should blow. And this they do and intend. But, in the mean season, this follows, (which, peradventure, they do not perceive,) that the wind is more contracted, and strikes more sharply.
9. What may be added to human industry in this, I cannot perceive, unless the figure of the sails be changed, and some sails be made which shall not swell round, but, like a spur or a triangle, with a mast or piece of timber in that corner of the top, that they may contract the wind more sharply, and cut the outward air more powerfully. And that angle (as we suppose) must not be altogether sharp, but like a short obtuse triangle, that it may have some breadth. Neither do we know what good it would do, if there were, as it were, a sail made in a sail; if, in the middle of a greater sail, there were a kind of a purse, not altogether loose, of canvass, but with ribs of wood, which should take up the wind in the middle of the sail, and bring it into a sharpness.
10. The third fountain or original of impulsion, is in the place where the wind hits, and that is twofold; for, from the fore side of the ship the impulsion is easier and stronger than on the hinder part; and from the upper part of the mast and sail than from the lower part.
11. Neither seems the industry of man to have been ignorant of this, when, in a fore-wind, their greatest hopes have been in their foremasts, and in calms they have have not been careless in hoisting up of their topsails. Neither, for the present, do we find what may be added to human industry in this point, unless concerning the first we should set up two or three foremasts, (the first upright and the rest sloping,) whose sails shall hang downward; and, as for the second, that the foresails should be enlarged at the top, and made less sharp than they usually are: but, in both, we must take heed of the inconvenience of danger, in sinking the ship too much.
The Motion of Winds in other Engines of Man's
1. The motion of windmills hath no subtilty at all in it; and yet, usually, it is not well explained nor demonstrated The sails are set right and direct opposite against the wind which bloweth. One side of the sail lies to the wind, the other side by little and little bends itself, and gets itself away from the wind. But the turning and continuance of the motion is always caused by the lower part, namely, that which is farthest from the wind. But the wind, overcasting itself against the engine, is contracted and restrained by the four sails, and is constrained to take its way in four spaces. The wind doth not well endure that compression; wherefore, of necessity it must, as it were, with its elbow hit the sides 2 Q