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song before Ignition. It is easily misceable with other Metals, and greatly increases their Sound and Elasticity. It is chiefly dug in Cornwal, and its Glebe or Ore is a beavy spongeous Stone. (6.) Lead ; this is next to Gold in Weight, but the Lead. softest and most flexible of all Metals; as also the most fusible, leaft sonorous and elastic of all others. It is sometimes found pure, but oftner in Mineral Ore, which is a fort of blackish fat Earth difficult to fuse.

MERCURY is by some reckon'd among the Mercury. Metals : It is the beaviest of all Bodies but Gold. It is the most fluid Body in Nature, and therefore divisible into the minutest Particles. It is found capable of the greatest Degree of Cold and Heat, but is yet uncapable of Congelation or Freezing. It enters the Pores of almost all Bodies, and disfolves in moft Acids. It is next to Gold in Purity ; and is extremely volatile. It is found in Mines, and sometimes pure, running in Veins and Streams about the Mine, and is then call'd Virgin-Mercury.

STONES make the next Class; these are Stores. commonly distributed into Vulgar and Precious Vulgar. Stones ; of the first sort are Marble, Flint, Free

Precious. Stone, Pumice-Stone, Talk, Chalk, common Stones, Pebbles, &c. Precious Stones, which are callid Gems or Jewels, are of divers Distinctions, some being transparent, as the Adamant or Diamond, Crystal, and Beryi : Some are variously colour'd, and brillant; as the Carbuncle, Jacinth, Chrysolite, Smaragdus, Topaz, Amethyst, Achate, Jasper, Ruby, Granate, Onyx, Sardonyx, Sapphire, and a few others of less Note. Of all which see an Account in the Philosophical Grammar.

EXUVIÆ, which make the last Head of Exuvia. Mineralogy, are all those Shells and Parts of Animals, which are often found in the Bowels of the

Earth :

Earth: As the Echini, Glossopetre, Cockles, OysterShells, Turbens, Scallops, Bones &c. petrified, or preserv'd from Corruption thro' Ages past, and very probably most of them from the Flood, when the Exuvie of marine &c. Animals were by the general Inundation brought upon and mix'd with the superior Part of the Earth, and which in Time harden'd into the Substance of

Stone. Phytology.

PHYTOLOGY; this will be the Subject of an entire Discourse under the Title BOTANY,

next following, which therefore see. Zoology.

ZOOLOGY ; this is that Part of general Geography, which treats of the Nature, Kinds, and

Species of Animals An Animal An Animal is an organized Body, endued with defined. the Powers of Sensation and Thought, and of co

luntary local Motion. This is the most exalted Kind of all terrestrial Beings, and in which there are many Gradations, which are the Subjects of as many Branches or Subdivisions of Zoology;

and these are as follows: (1.) Anthropography, The Parts of Zoology.

which treats of the Nature and Parts of the Human Body, and is the proper Subject of Anatomy, which see. (2.) Zoography in particular, which treats of the Nature of Beasts or Brutes; as Horses, Kine, Sheep, &c. (3.) Ornithography, which treats of the Nature of Birds or Foul. (4.) Ichthyography, or the Doctrine of Fijhes, which considers their Nature, Kinds, and Parts. (5.) Entomatography treats of Insekts, which are (quasi insesia ) as it were cut in sunder, and the two Parts join’d by a small Thread or Neck; as in Arts, Flies, Bees, &c. (6.) Herpetography, or the Doctrine of Reptiles, or that Tribe of Creatures which move with a sinuous, vermicular, or creeping Motion, and neither walk nor leap, as do the other Species above mention’d; such as Worms,

Snails, Snails, Caterpillars, &c. (7.) Zoopbytography treats of such Creatures as are a kind of Medium between Vegetables and perfeEt Animals, or partake of both in some measure; as all SbellAnimals: As Oysters, Cockles, Snails, &c. which resemble a Plant in being fix'd to some other Body, viz. their Shell; and an Animal, as having Sense, Thought, and Motion. Concerning all these the Reader may see a short Survey in the Philosopbical Grammar, or consult the larger Works of Naturalists.

HYDROGRAPHY delivers the Doctrine of Of Hydrograthe Sea, and all kinds of Waters. In the Sea we

pby.

The Sea. consider, (1.) Its Figure, which, since the Earth

Its Figure. is known to be of a round or globular Figure, must needs be convex or spherical likewise, according to the known Laws of Fluids; which also is demonstrated by failing on its Surface. (2.) Its Extent, or Quantity of Surface: 'Tis im- Exteri. possible nicely to determine this; but 'tis well known to be above two Thirds of the Surface of the whole Earth. (3.) The Depth thereof; this Depth. is various in different Parts, being in fome Places unfathomable, in others to i, u, l'o, 216, 45 English Miles deep ; whence it appears that the Depths of the Sea bear some Proportion to the Heights of Mountains on the Earth. (4.) Its Salt ; Saltness. this is supposed to arise from vaft Rocks, Mountains, and Mines of Salt dispersed over the Bottom of the Sea; which being continually diluted, is as constantly mixing with its Waters ; which therefore can never lose their falt Quality. (5.) The Tide, or Flux and Reflux, callid the Tides. Flowing and Ebbing of the Sea : This is known to arise from the Attraction of the Moon principally ; sometimes the Attraction of the Sun contributes thereto, as in Conjunétions and Oppositions, and then the Tides of course rise bigber, and are

Spring and
Neap Tides.

two Tides

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call’d the Spring-Tides. On the contrary, in the Quadratures the Moon's Attraction is diminish'd by the Sun's, and then the Tides flow lower, and

are call'd the Neap-Tides. How we have The Waters perpendicularly under the Moon

are in the upper Hemisphere most attracted, in each Day.

the lower one the least attracted of all other Parts of the Sea's Surface; and therefore in both Cases the Water will become lightest in these Places, and consequently will there tumify and rise highest, and so occasion two Tides opposite to each other ; which will successively pass any Meridian

at the Distance of twelve Hours time. The Difference

The Forces of the Moon's and Sun's Attraof Spring and Etion are to each other as 51 to 10; the Sum and Neap Tides. Difference of these Numbers are 61 and 41, and

therefore the Spring-Tides caused by the Sun will be to the Neap-Tides, caused by the Differences of these Forces, as 61 to 41, or as 6 to 4; that is, the former are one third Part greater than the latter : Or, if the Sun can raise one Foot eleven Inches, the Moon will raise it nine Feet seven Inches ; and both together in the Spring-Tides about eleven Feet and a half, but in Neap-Tides only about seven Feet and a half. And so much for a general Notion of the Tide, which admits

of great Variety and Exceptions. Of Springs.

SPRINGS or FOUNTAINS are the next

thing to be considered. They are generally recTemporary.

kon'd of two Sorts, viz. (1.) Temporary, which run only for a time, or in Winter, and dry up in the Summer. These arise from great Rains, which falling on the higher Parts of Land, enter the Crevices of the Earth, and run thro' various subterrancan Veins and Channels, till they find Vent in the Surface of some lower Part, where

they bubble up and iffue forth in Streams. (2.) Perennial. Perennial, which constantly run all the Year round.

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These are supposed to derive their Waters from
the Ocean, by Ducts and hollow winding Pas-
fages thro' the Bowels of the Earth to various
Parts of its Superficies, where they burst forth
as do the others: Tho' many will have it that
all Springs have their Waters, if not wholly, yet
principally from Rain. But so great is the Con-
troversy about these Things, that I shall say no
more of it here.

RIVERS are said to owe their Original to Rivers and
many Causes; as (1.) Great Springs gushing out their Causes.
of the Earth in large Streans and Torrents,
which force their Way thro' the Country to the
Ocean. (2.) The several lesser Streams from di-
vers Springs uniting, form a larger ; and the
Confluence of several of these larger Brooks or
Streams make one great Current or River. (3.)
Vast Defluxions of Rain, melted Snow, condensed
Vapours, &c. from the sides of high Mountains,
tear up the Earth, and form Channels for the
largest Rivers in the World, as the Danube, the
Po, &c.

LAKES are those Collections of Waters, Lakes whence. which are stagnant in the Cavities of the Earth's Surface. Of these fone have their Rivers which discharge themselves therein ; sonie proceed from Rain and Snows which fill those Hollows. Others are nourished by various Springs rising therein : And lastly, others have a Communication with, and receive their Waters from the Sea; which is manifest in Salt Lakes, as that of Haerlem, &c. Those Lakes send out large Rivers, which are supplied with subterranean Streams and Fountains: And those which receive large Rivers, and send out none, must have what's more than fufficient to fill them convey'd from them by Conduits under Ground,

of

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