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is, not that they move towards the poles, but are pointed and turned towards the poles. For since every revolving sphere, which has fixed poles. participates of the nature of movable and fixed; after, by its consistency or self-determining nature, the rotatory force is bound up, still the force and tendency to direct itself remains, is augmented and gathered into one; so that direction and verticity to the poles in hard bodies is the same with the revolution on their poles in fluids.
and powerful tides; but if in the opposite direc- | fixed bodies can agree with liquid and fluid—that tion, weak and scarcely perceptible. For the Red Sea hath a considerable tide; and the Persian Gulf, with a yet more entire westward direction, a still stronger. But the Mediterranean, the greatest of all gulfs, and its parts, the Tuscan, Pontic, and Propontic Seas, and in like manner the Baltic, all which tend eastward, are almost destitute of tide, or have only languid ones. But this difference is most conspicuous in certain parts of the Mediterranean, which, so long as they tend eastwards or turn towards the north, as in the Tuscan Sea and the others we have mentioned, are pacific and without much tide. But, after getting a westerly direction, which takes place in the Adriatic, it requires a remarkably large tide. To which we may also add this, that in the Mediterranean the slight reflux which is found begins from the ocean, the flow from the opposite direc-water, as in the general deluge; we conceive the tion, so that the water follows rather a course from the east than the natural refluence of the ocean. The three instances only we shall use for the present, in reference to this second inquiry.
There may be added to these another species of proof, agreeing with those already advanced, but of a more difficult nature. It is this: that an argument may be sought for proof of this motion from east to west, not only from the consenting motion of the heavens, of which we have already spoken,-where this motion is, as it were, in full flower and strength,-but also from the earth when it seems wholly to cease; so that it is really a direction of the universe, and pervades all things from the zenith to the interior parts of the earth. Now, we apprehend that this conversion takes place from east to west (as in reality it is found to do) upon the south and north poles. And Gilbertus has, with great care and accuracy, accomplished for us this discovery, that the whole earth and nature, so far as we call it terrestrial, have an inclination or popularity not softened down, but rigid, and, as Gilbertus himself calls it, robust, latent, but betraying itself in many nice experiments towards the north and south. And this observation we thus modify and correct, that this ought to be asserted only of the exterior formation about the surface of the earth, and ought not to be extended to the bowels of the earth; for that the earth is a magnet was at one time conceived,-a light imagination,-for it can not be that the inward parts of the earth resemble any substance which the eye of man hath seen: since all the substances among which we live are loosened, subdued, or broken up by the sun and heavenly bodies, so that they cannot possibly agree with those which have had their seat in a place where the influence of the heavenly bodies does not penetrate;-but, which is our present subiect, the more superficial crusts or formations of the earth appear to agree with the conversions of the sun. air. and waters, as far as solid and
The third inquiry remains. Whence and how ariseth that reciprocal action of the tides, once in six hours, which coincides with a quarter of the diurnal motion, with that difference to which we have adverted. To understand this, let us suppose that the whole globe was covered with
waters, as forming a complete and unbroken globe, would always roll in a progression from east to west each day to a certain extent: not certainly a great space, on account of the remission and deliberation of that motion as it approaches the earth, seeing the waters were nowhere obstructed or confined. Let us suppose, again, that the whole land was an island, and that it extended longitudinally between south and north, which confirmation and position most restrain and obstruct the motion from east to west; we think that the waters would keep on in their direct and natural course for a certain time, but, reverberated by the shores of that island, would roll back in equal intervals; that there would be, therefore, only one influx of the sea a day, and in like manner only one reflux, and that to each of these about twelve hours would be apportioned. And let us now suppose what is true and matterof-fact, that the land is divided into two islands, those, namely, of the new and old world; for Australia, by its position, does not much alter the effect; as neither does Greenland nor Nova Zembla, and that these two islands extend through nearly three zones of the world, between which two cceans, the Atlantic and Southern, flow, and these nowhere find a thoroughfare, except towards the poles; we think it necessarily follows, that these two ramparts impart and communicate the character or double reaction to the entire mass of waters. Whence arises that motion in the quarter of a day, so that the waters being cooped in on both sides, the ebb and flow of the sea would become visible twice a day, since there is a double advance, and also a double recoil. Now, if these two islands were extended through the waters like cylinders or columns, of equal dimensions, and with rectilinear shores, that motion might be easily perceptible, and might be pointed out to any one, which now seems to be perplexed and obscured by so great a variety of position of land and sea. For it is not difficult to form some
conjecture what degree of velocity it is proper to ascribe to that motion of the waters, and what distances it may describe in one day. For, if there be selected, in order to form a judgment of this matter, some of those coasts which are less mountainous, or low lying, and which are contiguous to the open sea, and then the measure of the space of the globe interjacent between the extreme points of the flux and reflux, and that space be quadrupled on account of the four movements of the tide each day, and that number again doubled on account of the tides at the opposite shores of the same ocean; and to this number there be something added over and above on account of the height of the shores, which always rise to a certain elevation above the channel of the sea; that calculation will give the space which this sphere of water, were it free from obstruction, and moving in progression round the enveloped globe of earth, would describe in one day, which certainly would not be great.
Now, with respect to that difference which coincides with the measure of the moon's motion, and forms the period of a lunar month; we think that the explanation is this, that the period of six hours is not the exact measure of this reaction, just as the diurnal motion of any of the planets is not accomplished in twenty-four hours precisely, and least of all that of the moon. Wherefore, the measure of the ebb and flow of the tide is not a quarter of the motion of the fixed stars, which is twenty-four hours, but a quarter of the diurnal motion of the moon.
Let it be inquired, whether the hour of the tide on the coast of Africa be before the hour of tide about the Straits of Gibraltar. Let it be inquired whether the hour of the tide about Norway is before the hour of the tide about Sweden, and that, in like manner, before the hour of the tide at Graveling?
Let it be inquired, whether the hour of the tide on the coast of Brazil be before the hour of the tide on the coast of New Spain and Florida? Let it be inquired, whether the hour of the tide at the shores of China is not found nearly the same with the hour of tide on the coast of Peru,
and with the hour of reflux on the coast of Africa and Florida?
Let it be inquired, how far the hour of tide on the coast of Peru differs from the hour of tide at the coast of New Spain; and particularly what are the differences of the hour of tide at either shore of the Isthmus of Darien, in America; again, how far the hour of tide on the coast of Peru corresponds with the hour of tide on the coast of China?
Let it be inquired respecting the largeness of the tides on different coasts, not merely respecting their periods or hours. For, although the largeness of tides is generally caused by the depressions of the shores, yet, notwithstanding, they are closely connected with the true principle of the motion of the sea, according as it is favourable or adverse.
Let inquiry be made with respect to the Caspian sea, which is formed by considerable bodies of water locked up, without any outlet into the ocean, if they are subject to ebb and flow, and what? our conjecture being that the waters of the Caspian Sea may have one tide a day, not two, and such that the eastern shores of it are deserted by the sea, while the western are over. flowed.
And let inquiry be made, whether the increase of the tide at new and full moons and at the equinoxes, takes place at the same time in different parts of the world, (and when we say at the same time, we do not mean at the same hour, for the hours vary, according to the rapidity of the waters' motion towards the shores, as we have said,) but in the same day.
Limits. The inquiry is not extended to a full explanation of the harmony of the monthly motion of the sea with the moon's motion, whether that takes place from a subordinate or a joint cause.
Relations. The present inquiry is connected with the inquiry whether the earth revolves with the diurnal motion of the heavens. For if the tide is, so to speak, the last stage of the gradual diminution of the diurnal motion, it will follow, that the globe of the earth is immovable, or at least that its motion is slower by far than that of the water. W. G. G
THE ABECEDARIUM NATURÆ,
BY ARCHBISHOP TENNISON.
PUBLISHED IN THE BACONIANA, 1679.
THE SAME IN ENGLISH BY THE PUBLISHER.
A Fragment of a Book written by the Lord Verulam, and entitled, The Alphabet of Nature.
SEEING SO many things are produced by the earth and waters; so many things pass through the air, and are received by it; so many things are changed and dissolved by fire; other inquisitions would be less perspicuous, unless the nature of those masses which so often occur, were well known and explained. To these we add inquisitions concerning celestial bodies, and meteors, seeing they are some of greater masses, and of the number of catholic bodies.*
The sixty-seventh inquisition. The threefold Tau, or concerning the earth.
negatives subjoined to affirmatives, conduce much to the information of the understanding: it is fit that an inquisition be made concerning being, and not being. That is the seventy-third in order, and reckoned the fourfold Alpha.
Conditions of beings. The fourfold Alpha; or, concerning being, and not being.
Now, possible and impossible, are nothing else but conditions potential to being, or not potential to being. Of this the seventy-fourth inquisition consists, and is accounted the fourfold Beta.
Conditions of beings. The fourfold Beta; or, concerning possible and impossible.
Also, much, little; rare, ordinary; are conditions potential to being in quantity. Of them let the seventy-fifth inquisition consist, and be acThe threefold counted the fourfold Gamma.
The sixty-eighth inquisition. The threefold Upsilon, or concerning the water.
The sixty-ninth inquisition. Phi, or concerning the air.
The seventieth inquisition. The threefold Chi, or concerning the fire.
The seventy-first inquisition. The threefold Psi, or concerning celestial bodies.
The seventy-second inquisition. The threefold Omega, or concerning meteors.
Conditions of Entities.
There yet remain, as subjects of our inquiry, in our alphabet, the conditions of beings, which seem, as it were, transcendentals, and such as touch very little of the body of nature. Yet, by that manner of inquisition which we use, they will considerably illustrate the other objects.
First, therefore; seeing (as Democritus excellently observed) the nature of things is in the plenty of matter, and variety of individuals large, and (as he affirmeth) infinite; but in its coitions and species so finite, that it may seem narrow and poor; seeing so few species are found, either in actual being or impossibility, that they scarce make up a muster of a thousand; and seeing
See the distribucion, in 1. 2, c. 3, de Augm. Scient. p. 134,
Conditions of beings. The fourfold Gamma; or, concerning much and little.
Durable and transitory, eternal and momentary, are potential to being in duration. Of these let the seventy-sixth inquisition consist, and be called the fourfold Delta.
Conditions of beings. The fourfold Delta; or, concerning durable and transitory.
Natural and monstrous, are potential to being, either by the course of nature, or by its deviations from it. Of these let the seventy-seventh inquisition consist, which is accounted the fourfold Epsilon.
Conditions of beings. The fourfold Epsilon; or, concerning what is natural or monstrous.
Natural and artificial, are potential to being, either with or without the operation of man. Of these let the seventy-eighth inquisition consist, and be accounted the fourfold Zeta.
Conditions of beings. The fourfold Zeta; or, of that which is natural and artificial.
We have not subjoined examples in the explication of the order of this our alphabet: for the inquisitions themselves contain the whole array of examples.
It is by no means intended, that the titles, ac
cording to which the order of this alphabet is disposed, should have so much authority given to them, as to be taken for true and fixed partitions of things. That were to profess we already knew the things after which we inquire; for no man does truly dispose of things into their several classes, who does not beforehand very well understand the nature of them. It is sufficient, if these titles be conveniently adapted to the order of inquiry; the thing which is at present designed.
The Rule or Form of the Alphabet.
After this manner we compose and dispose our alphabet:
We begin solely with history and experiments. These, if they exhibit an enumeration and series of particular things, are disposed into tables; otherwise, they are taken separately and by
But, seeing we are often at a loss for history and experiments, especially such as are luciferous, or instructive, and, as we call them, instances of the cross;* by which the understanding might be helped in the knowledge of the true causes of things: we propose the task of making new experiments. These may serve as a history in design. For what else is to be done by us who are but breaking the ice?
For the mode of any more abstruse experiment, we explain it, lest any mistake arise about it; and to the intent, also, that we may excite others to excogitate better methods.
Also, we interspect certain admonitions and cautions concerning such fallacies of things, and errors in invention, as we meet with in our way. We subjoin our observations upon history and experiments, that the interpretation of nature may be the more in readiness and at hand.
Likewise, we lay down canons (but not such as are fixed and determined) and axioms which are, as it were, in embryo: such as offer them
See Nov. Organ., 1. 2., Aph. 36.
selves to us in the quality of inquirers, and not of judges. Such canons and axioms are profitable, though they appear not yet manifest, and upon all accounts true.
Lastly we meditate sometimes certain essays of interpretation, though such as are low and of small advance, and by no means to be honoured (in our opinion) with the very name of interpretation.
For, what need have we of arrogance or imposture, seeing we have so often professed that we have, not such a supply of history and experiments as is needful; and that, without these, the interpretation of nature cannot be brought to perfection. Wherefore, it is enough for us if we are not wanting to the beginning of things.
Now, for the sake of perspicuity and order, we prepare our way by avenues, which are a kind of prefaces to our inquisitions. Likewise, we interpose bonds of connection, that our inquisitions may not seem abrupt and disjointed.
Also, we suggest for use some hints of practice. Furthermore, we propose wishes of such things as are hitherto only desired and not had, together with those things which border on them, for the exciting the industry of man's mind.
Neither are we ignorant that those inquisitions are sometimes mutually entangled; so that some things of which we inquire, even the same things belong to several titles. But we will observe such measure, that (as far as may be) we may shun both the nauseousness of repetition, and the trouble of rejection, submitting, notwithstanding, to either of these, when, in an argument so obscure, there is necessity of so doing, in order to the more intelligible teaching of it.
This is the form and rule of our alphabet.
May God, the creator, preserver, and renewer of the universe, protect and govern this work, both in its ascent to his glory, and in its descent to the good of mankind, for the sake of his mercy and good will to men, through his only Son, Immanuel, God with us.
CATALOGUE OF BODIES, ATTRACTIVE AND NOT
BY ARCHBISHOP TENNISON.
If there be made a turn-pin of any metal, after the fashion of a magnetic needle, and amber be applied to one end of it, after having been gently rubbed, the pin will turn.
Amber heated by the fire, be it warmish, hot, or set on fire, it does not draw.
A little bar of iron red-hot, flame, a lighted candle, a hot coal, put nigh sheaves (or straws) or turn-pins, (or compass needles,) do not draw.
Amber, in a greater mass, if it be polite, draws, though not rubbed in a lesser quantity, and in a less polite mass, it draws not without rubbing.
Crystal, lapis specularis, glass, and other such electric bodies, if burned, or scorched, draw not. Pitch, the softer rosin, benjoin, asphaltum, camphire, galbanum, ammoniac, storax, assa, these draw not at all when the air is hot: but when it is cooler, they draw weakly, and so that we can just perceive them to do so.
applied to a shiver, or a compass-needle, draws best of all.
The electric virtue is as vigorous, for a time, in its retention, as it was in its first attraction. Flame (amber being put within the sphere of its activity) is not drawn by it.
A drop of water, amber being applied towards it, is drawn into a cone.
If electric bodies be rubbed too hard, their attraction is thereby hindered.
Those bodies, which in a clear sky do scarce draw, in a thick air move not at all.
Water put upon amber choketh its attractive force, though it draweth the water itself.
Fat* so encompassing amber, that it toucheth it, takes away its attraction; but being so put betwixt it and the object to be drawn, as not to touch it, it doth not take it away.
Oil put upon amber, hinders not its motion: Reeking air, blown-up amber, &c., from the neither doth amber, rubbed with the finger moistmouth, or from a moister atmosphere, chokethened with oil, lose its attractive virtue. the attractive virtue.
If a paper, or a piece of linen, be put between amber and chaff, there is no motion, or attraction made.
Amber, or other electrics, warmed by the sunbeams, have not their attractive virtue so awakened, as by rubbing.
Amber rubbed, and exposed to the beams of the sun, retains its attractive force the longer; and does not so soon lose it, as it would do in the shadow.
Amber, jeats, and the like, do more strongly excite, and longer retain the objects they draw, although the rubbing be but little. But diamonds, crystal, glass, ought to be rubbed longer, that they may appear hot, ere they be used for attraction.
Flames nigh to amber, though the distance be very small, are not drawn by it.
Amber, &c., draw the smoke of a lamp newly extinguished.
Amber draws smoke more strongly when it Heat derived from a burning-glass to amber, comes forth, and is more gross; and more weakly, &c., does not help its attraction.
Sulphur, and hard wax, set on fire, do not draw.
Amber, when, immediately after rubbing, it is
when it ascends and becomes thinner.
A body drawn by electric bodies, is not manifestly altered, but only leans itself upon them.
* For by Sarca, I suppose, he meaneth Sarcia.