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YET in some Places there are higher Tides at the Full Moon than at the New, which I cannot account for, unless they be the Effects of it's greater Light at that time. Nor can it be otherwise explained, why at the Full Moon Vegetables and Animals are impregnated with a greater quantity of Sea Moisture, than at die New, tho' even then the Tides are every whit as high. It is very wonderful what one Twist, a Dutchman* relates in his Description of India, He says, that in the Kingdom of Guzarai (where he lived many Years) their Oysters, and Crabs, and other ShellFifh, are not so fat and juicy at the Full Moon as at the New, contrary to their Nature in all other Places. Nor is it less admirable, that on the Coast of the fame Kingdom, near the Mouths of the River Indus, the Sea swells, and is troubled, at the New Moon, when not far from hence, viz. in the Sea of Calicut the greatest Rife of the Waters is at the Full. But it is requisite that we should have repeated Enquiries and Observations about these Matters, before we pretend to solve their Phænomena,

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PROPOSITION XIII.

The Flux and Reflux of the Sea varies with the Seasons of the Tear, and the Tides are observed to he highest about the Equinoxes; i. e. at the Spring and Fall j but lowest at the Solstices,

DES Cartes pretends to account for this Phae> nomenon by his Hypothesis, but I cannot ap-? prehend his Meaning by his Words, nor how it Can be deduced from it (h). It is probable, that the Sun and the general Winds may contribute much

(b) Sit the true Reason ofth'u in Artie. 3. f/Nott (fj above.

to raise these Tides, when, in the Equinoxes, the Sun is vertical tp the Ocean in the middle of the 'torrid Zone, and therefore may cause both the Wind and Water so rage, and the former to agitate the latter, The contrary of which may happen about the Solstices, Or we may fay, that thele extraordinary Tides then happen by the fame Reason, and proceed from the same Cause that frequent Rains and Inundations proceed from in these Seasons.

PROPOSITION XIV,

Jn some Parts of the Ocean, Bays, and Shores, the Tides ebb and flow very high; and in others but

low: and in some few Places there are no sensible

Tides at all.

THOSE Places have the greatest Tides j t2 which are in the Torrid Zone between the Tropics, where the Moon, being almost constandy vertical, presses the Water with greater force \ 2. those which lie directly East and West with their Collaterals; 3. those Bays that are long and narrow s 4. those Places where there are but few Islands or Forelands.

THE Tides are therefore greater or less in a Place, according as it is situated or extended.

THE greatest known Tides are observed in the Bay of Guzarat, at one of the Mouths of thfc River Indus, and has struck many with Admiration. The Water there recedes from the Shore very quick, and leaves it uncovered for a great Space so that this Bay is, not without Reason, thought to be the same into which Alexander the Great sailed, when he attempted to transport his Army by Sea into India, but was hindered, as it is reported, by the Sea which retired quick from the Shore, and left all his Ships a-ground, so that he could not proceed further, but thought that the Gods had there fixed Bounds to his Expedition. This Story is reported for a Truth by the Inhabitants of Cambaya, The Cause of -this is the fhallowness of the Chanel, which makes the Water in it's Ebbing leave so much more .Ground uncovered, tho' perhaps some other Cause may conspire with this. , AT the Town of Daman, not far from Sur at in India, the Tide rises and falls two Fathoms and a half, and the Sea recedes .from the Shore half a German Mile.

..-.IN die Bay of Cambaya the Tide flows five (or as some fay seven) Fathoms high, which violent Flux causes many Ships to be lost by unexperienced Seamen; for at the Ebb, when the Water falls back, they are frequently split upon the Rocks.

* UPON the Shores and Bays at the Magellanic 'Streights, there is no constant Time observed between the Tides, which ebb and flow irregularly, sometimes in three Hours, and sometimes in twelve JHours which variety is caused by the violent breaking of the Sea into these Streights, and the frequent Agitation of it by the Winds. .. j ,; PRODIGIOUS high Tides are observed about Malacca, and in the Streights, of Sunda. 'IN the, Arabian Gulph, or Red-Sea, the Tide of Ebb is so great, that as some of the Antients have writ, (quoted by ScaUger) Moses,, and the Israelites, might", at low Water, have passed thro' it without a Miracle. But this is false, for it never ebbs so much as to leave the Chanel dry.

IN Button's Bay, near Hudson's Streights, when Mr Thomas Button, an Englishman, wintered there in the Latitude of 57 Degn North Latitude, he observed the Tide of Flood to rise fifteen Foot ah4

"above: above : and in the Latitude of 60 Degr. the Summer after, he found it to come up to the same Height;' tho' in neither Hudson'% nor J ames'% Bay it rises much above two Foot.

T H E R E are prodigious high Tides upon the Goast of China, and about the Islands of Japan.

A T Panama, a Town on the Coast of America, the Pacific Sea flows very high, and immediately ebbs again •, at the Full Moon the Agitation is so great that it drives the Water into the Houses of the Town. All along this Shore the Tides of she great South Sea are strangely high; so that in their Reflux they retreat two Miles of Ground,' and in some Places the Water falls of out Sight.

I N the Bay of Bengal, on the Shore of Siam, the Tide riles fifteen Foot.

B U T in the Mediterranean Sea, which flows from West to East thro' the Streights of Gibralter, there is no sensible Tide at all; because it's Entrance is situated opposite "to that Point, to which the Ocean Sea in general flows. It may perhaps Increase a little, but in the main it is not sensible, 6nly in the Gulph of Venice there is a small Agifation perceived, by reason of the great length and narrowness of the Bay, which, in the broader Parts of the Mediterranean, is no where perceptible. Therefore the Flux and Reflux of the Sea was unknown to the Grecians, and also to the Romans in the Time ofScipio Africanus ; and therefore when they found it . in other Places, accounted it a Miracle j as appears from the forementioned Expedition of Alexander the Great, and the Wars of Scipio with Carthage; but in Cicero's Time this was well enough known to the Romans. A small Tide is observed at Marseilles in France, and an inconsiderable Rising is perceived along the Coast of Barban.

IN

IN the Baltic Sea, and all over the northern Ocean beyond England and Norway the Tides are not in the least perceptible; nor in the northern Parts of the Pacific Ocean (j). The Reason is not well known, unless we fix it upon the great Distance these Seas are from the way of the Moon, and their being extended from West to East, and North-east, with the many Islands and Forelands, all which conspire to obstruct the Flux of the Tides in these Places. But this cannot be said of Hudson's Bay j which is properly extended from East to West, to receive the Flux of the Tides j and therefore it is no Wonder if they are much more remarkable here than in the Baltic, or in the northern Ocean.

PROPOSITION XV.

The Flux of the Sea is forced by a strong Impulse but the Reflux is the natural Motion of the Water*

THE Flux is caused by the Pressure of the Moon, or the celestial Matter, between it and die Sea, and continues no longer than the Cause forces it: but in the Ebb, the Sea only flows from a higher to a lower Place, which is the natural Motion of the Water.

(/) The Tides are very small on the Coast of Nova Zembla the

in several Parts of the Northern Water was observed by C*pt.

Ocean, yet they may be felt in Wood to rise eight Foot. See

some particular Places. Thus Note {a) on Chap. 8- above.

LEMMA

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