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less able to resist the Eruption. To which I anfwer, that tho' this is possible, yet it cannot be proved either by Reason or Experience, so neither can the contrary, therefore this Problem is a Dilemma, or doubtful. That there are indeed subterraneous Receptacles and Cavities in some Parts of the Bottom of the Sea we cannot deny, because in some Parts it is of an immense Depth, where the neighbouring Places are but shallow; but if this were admitted it will not follow, that the Water runs thro’ these Passages, or that they extend from one Chanel of the Ocean to another: or even if they were, since they are not in all Places, and since these external Causes operate sometimes in one, and sometimes in another Part of the Ocean, it will not be granted, that there are perpetual Springs of the Ocean in any one Place, but that the Water flows sometimes from one Part of the Chanel, and sometimes from another, according to the Place and Continuance of the external Cause.
2. SOME may thus argue, that there is a continual Current of the Sea from North to South, between both sides of America and the Old World ; but that we cannot perceive a Current in any Place whereby the Water is conveyed towards the Northern Regions : therefore since the Flux is perpetual, and hath no apparent Source there, nor Conveyance thither, it is probable, that the Water flows to the North thro’ subterraneous Paffages, and issueth out at the Holes in the Bottom of the Chanel, as out of a Spring; from whence it returns again to the southward. There is another Cause taken from the former, viz. That the Sea-Water in the Torrid Zone is much heavier than in the Northern Re. gions, as we shall prove in Proposition 8, and 12; and therefore there is a greater Pressure and Force to push forward the Water thro' the Passages there, than there is to resist it at the Northern End of the
Intercourses, Intercourses, where, for want of an equal Pressure, it breaks out at the Holes in the Bottom of the Chanels. To this we answer, that the Flux of the Ocean from the North is not so great as is supposed, and as the Ancients imagined ; (who would have the Water to flow from the Pole thro’ four Chanels, as is represented in some old Geographical Maps ;) nor are the Currents constant, but only frequently observed, by reason of the frequent North-Winds, and the great quantities of Snow and Rain which very often raise the Waters, and cause them to flow towards the South. And further, in other Parts another Motion of the Sea is observed, of which see the following Chapter
3. IT is no Notion, but a real Truth, that all the Springs of Rivers, which flow into the Sea, are Springs of the Ocean : For since there is in Process of Tinie a vast quantity of Water poured into the Sea, no doubt but it returns from the Ocean to the Heads of the Rivers thro’ subterraneous Passages, or by Dew and Rain. We fhall not contend about this; for we do not, in the Proposition, mean such Springs as these; but whether there are Springs in the Caverns of the Earth, under the Chanel of the Sea, which supply the O. cean with Water.
4. IT appears probable, that there are such Springs in the Chanels of the Sea ; because there is found, in fome Places, fresh Water at the Bottom of the Sea, which must certainly arise from Springs in the very Chanel, Linschoten tells us, that in the Gulph of Ormus, near the little Inand Bareyn, there is brought up fresh Water, by the Divers, at four or five Fathoms depth ; and the like Springs are found at the Bottom of the Seas and Bays. To this we answer ; that there are but few such Springs found, and those not sufficient
to supply the Ocean with Water; besides the Question is not about such, as we said before.
FROM these Things it appears, that the Sea may be rightly said to have Springs in some Sense, tho’ different from what we mean by the Springs of Rivers ; in which Sense this Proposition ought to be understood. Hence also we know what to think of the Question ; Whether the Ocean be always one and the same, and constantly remains fo, or whether it be a Body whose Parts are consumed and renewed again perpetually.
The Saltness, or Salt Taste, of the Sea-Water proceeds
from the Particles of Salt which are mixed with it : but whence these Particles proceed, or how they are continued and increased, is uncertain.
EXPERIENCE proves the first part of this Proposition, for every Body knows that Salt is made either by evaporating Sea-Water with the Sun, or by boiling it with the Heat of our Fires. In Germany, and other countries, they make use of Fire to separate the Water from it. But in France, where the Sun is hotter, the Sea-Water is let into Pits or Ponds, where in a few Months, by the extream Heat of the Sun, it's fresh Particles are exhaled or evaporated, and it's falt ones are concreted and formed into Grains of Salt. Also upon the Shores of several Countries, as England, &c. there is gathered abundance of Bay-Salt, which the Sea (continually overflowing them) leaves daily in moist Particles, from whence the most subtile, or fresh, Parts are exhaled, and what is left becomes Heaps of Grains of Salt, whose Blackness is taken off by boiling; tho' this sort of Salt is washed away and diffolved from many Shores by
the the Violence of the Ocean, and therefore is nor found upon all Shores. And since this is a common Experiment which every one knows, Aristotle need not have instanced a false one (by letting down a Veffel of Wax into the Sea) to prove the Truth of this Proposition.
HENCE it appears,, that the true cause of the Saltness of Sea Water, is the Particles of Salt which are contained in it, and mixed with it. Therefore the Aristotelians, with their Mafter, fpeak improperly, and obscurely, when they assert that this Saltness is caused by the Water's being extreainly heated by the Rays of the Sun ; but of this we shall say more by and by.
BUT the chief Controversy is about the other part of the Proposition, viz, whence these Particles of Salt proceed ?
ARISTOTLE was of Opinion that the dry Exhalations, or Fumes, (which he thought were burnt, and of a saline Nature) being elevated from the Earth, and mixed with moist Particles, when they are turned into Rain, fall down with it into the Sea, and that from thence proceed the faline Particles, and the Saltness in the Sea-Water. These are his express Words in Lib. ii. Chap. vii. Meteor. And he takes a great deal of Pains to defend this Opinion, because by it he could shew a Reason why the Sea continues always salt.
OTHER Peripatetics (who also pretend to have Aristotle on their Side) assert, that the Sea is falt in itself, by reason of it's being perpetually fcorched with the Sun-Beams; and for this Reason they say it is fresher towards the Bottom, and falteft at the Surface, · BOTH these Opinions labour under such great Difficulties and Absurdities, that it is a Wonder fo many learned Men and Philosophers could be far tisfied with them. ...
THESE things may be objected against Aristotle's Hypothesis ; 1. That Rain-Water, according to this, ought to taste falt, upon the Ocean, which is contrary to Experience, for it is found not to taste falt at all. And Scaliger's Remedy for this is insufficient, who says, that it ought not to taste so at first, because the hot Vapour hath not had time to be condensed, being more rare, and also having lately descended from a colder Region of the Air ; but such Rain-Water hath been preserved several Days by Mariners, in which time it would certainly have tasted salt, if it had held any in it. 2. The less it rained the less salt would the Sea-Water taste, which is found to the contrary.
THE other Opinion hath these Absurdities: 1. It is false that the Sea is not so brackish nearer the Bottom ; for this only happens where Springs of fresh Water rise from the Bottom of the Chanel. 2. Experience shews that fresh Water doth not become salt by long boiling, or by being long exposed to the Sun. Scaliger likewise endeavours to obviate this Objection by a subtile Argument. He says that this happens so by reason of the smallness of the quantity of that Water which is used in the Experiment, which doth not thicken but is diffolved. But let us take ever fo great a Quantity, and put it over a gentle Fire, that the dissolution (into Vapours as he means) may be hindred, yet the Water will taste no more brackish than it did at first. 3. Lakes and Marshes, though they are constantly heated by the SunBeams, yet do not grow falt. Scaliger also would wave this Objection, saying, that this happens because of the continual Succession of fresh Water. But if we observe Lakes and Moraffes that are fed only by Rain and melted Snow, where there is no such Succession, we shall find VOL, I,