long before Ignition. It is eafily mifceable with other Metals, and greatly increases their Sound and Elafticity. 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. fofteft and most flexible of all Metals; as alfo the moft fusible, leaft fonorous and elaftic of all others. It is fometimes found pure, but oftner in Mineral Ore, which is a fort of blackish fat Earth difficult to fufe.

MERCURY is by fome reckon'd among the Mercury. Metals: It is the heaviest of all Bodies but Gold. It is the most fluid Body in Nature, and therefore divifible into the minuteft 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 fometimes pure, running in Veins and Streams about the Mine, and is then call'd Virgin-Mercury.

STONES make the next Clafs; thefe are Stones. commonly diftributed into Vulgar and Precious Vulgar. Stones; of the first fort are Marble, Flint, Free- Precious. Stone, Pumice-Stone, Talk, Chalk, common Stones, Pebbles, &c. Precious Stones, which are call'd Gems or Jewels, are of divers Distinctions, fome being transparent, as the Adamant or Diamond, Crystal, and Beryl: Some are variously colour'd, and brillant; as the Carbuncle, Jacinth, Chryfolite, Smaragdus, Topaz, Amethyst, Achate, Jafper, Ruby, Granate, Onyx, Sardonyx, Sapphire, and a few others of lefs Note. Of all which fee an Account in the Philofophical Grammar.

EXUVIE, which make the laft Head of Exuvia. Mineralogy, are all thofe Shells and Parts of Ani

mals, which are often found in the Bowels of the

Earth:

Phytology.

Zoology.

An Animal defined.

The Parts of
Zoology.

Earth: As the Echini, Gloffopetre, Cockles, Ofterfhells, Turbens, Scallops, Bones &c. petrified, or preferv'd from Corruption thro' Ages paft, and very probably moft of them from the Flood, when the Exuvie of marine &c. Animals were by the general Inundation brought upon and mix'd with the fuperior Part of the Earth, and which in Time harden'd into the Subftance of Stone.

PHYTOLOGY; this will be the Subject of an entire Difcourfe under the Title BOTANY, next following, which therefore fee.

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

AN Animal is an organized Body, endued with the Powers of Senfation and Thought, and of voluntary 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 Subdivifions of Zoology; and these are as follows: (1.) Anthropography, which treats of the Nature and Parts of the Human Body, and is the proper Subject of Anatomy, which fee. (2.) Zoography in particular, which treats of the Nature of Beafts or Brutes; as Horfes, Kine, Sheep, &c. (3.) Ornithography, which treats of the Nature of Birds or Fowl. (4.) Ichthyography, or the Doctrine of Fishes, which confiders their Nature, Kinds, and Parts. (5.) Entomatography treats of Infects, which are (quafi infecta) as it were cut in funder, and the two Parts join'd by a small Thread or Neck; as in Ants, Flies, Bees, &c. (6.) Herpetography, or the Doctrine of Reptiles, or that Tribe of Creatures which move with a finuous, vermicular, or creeping Motion, and neither walk nor leap, as do the other Species above mention'd; fuch as Worms, Snails,

Snails, Caterpillars, &c. (7.) Zoophytography treats of fuch Creatures as are a kind of Medium between Vegetables and perfect Animals, or partake of both in fome measure; as all ShellAnimals: As Oyfters, Cockles, Snails, &c. which refemble a Plant in being fix'd to fome other Body, viz. their Shell; and an Animal, as having Senfe, Thought, and Motion. Concerning all these the Reader may fee a fhort Survey in the Philofophical Grammar, or confult the larger Works of Naturalifts.

phy.

Its Figure.

HYDROGRAPHY delivers the Doctrine of Of Hydrograthe Sea, and all Kinds of Waters. In the Sea we The Sea. confider, (1.) Its Figure, which, fince the Earth is known to be of a round or globular Figure, muft needs be convex or spherical likewife, according to the known Laws of Fluids; which alfo is demonftrated by failing on its Surface. (2.) Its Extent, or Quantity of Surface: 'Tis im- Extent. poffible 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, 14, 15, 25, 4 English Miles deep; whence it appears that the Depths of the Sea bear fome Proportion to the Heights of Mountains on the Earth. (4.) Its Salt; Saltness. this is fuppofed to arife from vaft Rocks, Mountains, and Mines of Salt difperfed over the Bottom of the Sea; which being continually diluted, is as conftantly mixing with its Waters; which therefore can never lofe their falt Quality. (5.) The Tide, or Flux and Reflux, call'd the Tides. Flowing and Ebbing of the Sea: This is known to arife from the Attraction of the Moon principally; fometimes the Attraction of the Sun contributes thereto, as in Conjunctions and Oppofitions, and then the Tides of courfe rife higher, and are

call'd

Spring and
Neap Tides.

How we have
two Tides
each Day.

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.

THE Waters perpendicularly under the Moon
are in the upper Hemifphere most attracted, in
the lower one the least attracted of all other Parts
of the Sea's Surface; and therefore in both Cafes
the Water will become lighteft in thefe Places,
and confequently will there tumify and rife high-
eft, and fo occafion two Tides oppofite to each
other; which will fucceffively pafs any Meridian
at the Distance of twelve Hours time.

The Difference
THE Forces of the Moon's and Sun's Attra-
of 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, caufed by the Differences
of thefe 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 raife one Foot eleven
Inches, the Moon will raife it nine Feet feven
Inches; and both together in the Spring-Tides
about eleven Feet and a half, but in Neap-Tides
only about feven Feet and a half. And fo much
for a general Notion of the Tide, which admits
of great Variety and Exceptions.

Of Springs.

Temporary.

Perennial.

SPRINGS or FOUNTAINS are the next thing to be confidered. They are generally reckon'd of two Sorts, viz. (1.) Temporary, which run only for a time, or in Winter, and dry up in the Summer. Thefe arife from great Rains, which falling on the higher Parts of Land, enter the Crevices of the Earth, and run thro' various fubterrancan Veins and Channels, till they find Vent in the Surface of fome lower Part, where they bubble up and iffue forth in Streams. (2.) Perennial, which conftantly run all the Year round.

Thefe

These are fuppofed to derive their Waters from the Ocean, by Ducts and hollow winding Paffages 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 fo great is the Controversy about these Things, that I fhall fay no more of it here.

RIVERS are faid to owe their Original to Rivers and many Caufes; as (1.) Great Springs gufhing out their Caufes. of the Earth in large Streams and Torrents, which force their Way thro' the Country to the Ocean. (2.) The feveral leffer Streams from divers Springs uniting, form a larger; and the Confluence of feveral of thefe larger Brooks or Streams make one great Current or River. (3.) Vaft Defluxions of Rain, melted Snow, condenfed 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 thofe Collections of Waters, Lakes whence. which are stagnant in the Cavities of the Earth's Surface. Of these fome have their Rivers which discharge themselves therein; fome proceed from Rain and Snows which fill thofe Hollows. Others are nourished by various Springs rifing therein: And lastly, others have a Communication with, and receive their Waters from the Sea; which is manifeft in Salt Lakes, as that of Haerlem, &c. Thofe Lakes send out large Rivers, which are supplied with fubterranean 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