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which the Planets, both primary and secondary, per-
form their respektive Motions ; and that this Law
obtains in all the circulating Bodies of the Uni-
verse ; 'tis evident the Sun would observe it also,

did it really move round the Earth, as it appears
A Proof the
Sun does not

to do, in 365 Days : But that it does not observe moup round

it is plain, for the Moon moves about the Earth the Earth.

in 27 Days, and is 6o Semidiameters of the
Earth distant from us. Now the Square of 27 is
729, and of 365 is 133225; alfo the Cube of
60 is 216000; therefore say, As 729:133225
:: 216000 : 39460356, the Cube Root of which
is 340 nearly, which therefore should be the
Distance of the Sun in Semidiameters of the
Earth: But 'tis well known the real Distance of
the Sun is above 2000 Semidiameters; according
to which it could not turn round the Earth in less
than 5196 Years, if it observed the same general
Law which all the rest of the heavenly Bodies do.
Consequently the Earth moves round the Sun,
and not the Sun round it. This is called the

Annual or Yearly Motion of the Earth : Besides
The Annual
ard Diurnal which, at the fame time, it revolves about its
Motion of the own Axis once in 24 Hours, and is call'd the
Earth. Diurnal Motion, which is the Cause of Day and

Night, as the other is, in part, of the Seasons of
the Year: All which you have largely illuitrated

in my Philofophical Grammar. The Earth, as

Since then the Earth is a Body moving ? Planet, is round the Sun as its Center, it must be esteem'd situate in the third Orb from

a Planet as well as Mercury, Venus, Mars, &c. the Sun.

are for the very fime Reason ; and with respect
to them obtains its Place the third from the Sun
or Center, having Mercury and Venus below its

Orb, and Mars, Jupiter, and Saturn above it.
Otheinternal

The internal Substance or Constitution of Substance of the Earth is entirely unknown to us at all Depths * Earth. below the Surface. Some think the central Parts

are

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are possess’d by Fire, others say by Water, but others there place an immense Loadstone, from which those lesser Magnets we use derive there Virtue and wonderful Properties, as being Parts thereof, and acting in a perfect Conformity to its Nature : But these Things are uncertain. However, certain it is that the outward Shell or Crit of the Earth is composed of divers heterogeneous Substances, of different Gravities, dispofed, for the most part, in the Form of Beds, cal- Various Beds, led Strata, or Layers of Earth, Loam, Clay, Chalk, er Layers of Stones, Sand, Mineral and Metallic Ores, Sulphur, Moulds and Salts, &c. variously intermix'd together, as ap- pose the cutpears from the digging of a Well at Amsterdam zward Sbell. 232 Feet deep, where the Veins of the Earth, &c. appear'd as follows:

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Feet.

Feet.
Garden Mould,

7
White Loam,

4 An Example

thereof. Of Turf or Peat, 9 Of dry Earth,

5 Of soft Clay,

9 Of muddy Earth, I Of Sand, 8 Of Sand,

14 Of Earth,

4 Of Sandy Clay, 3 Of Clay,

Sand mix'd with Clay, 5
Of Earth, 4 Sea-Sand with Shells, 4
Of Paving Sand, 10 Clay,
2 Loam,

31

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102

Of Clay

Such is the Make of the outward Part of the
Earth, which yet is very different in different
Places. I now proceed to the two great Parts of
Geography before mentioned; and first of

SPECIAL GEOGRAPHY, which treats The Subject of of the terrestrial Part of the Earth's Surface, or Special Geothat we call Land. This admits of the following graphy divided Divisions, viz. (1.) Continents; which are large

Continents. and spacious Tracts of Land, comprehending divers Countries, Kingdoms, and States, all con

tiguous

into

tiguous to each other, and uninterrupted by Seas

or Water. Of these there are four, viz. Europe, Islands. Asia, Africa, and America. (2.) Islands; which

are Parts of Land entirely encompass’d with

Water ; such as Great-Britain, Ireland, &c. (3.) Peninsula's. Peninsula's ; which are Parts of dry Land every

where enclosed with Water, fave one narrow

Neck by which it is join'd to the Continent. Ifhmus's. (4.) Isthmus's are those Necks of Land which

join the Peninsula's to the main Land, and by

which People pass from one into the other. Promontories. (5.) Promontories; which are high Parts of Land

stretching out in the Sea, the Extremities whereof Mountains, are call'd Capes or Head-Lands. (6.) Mountains ;

these are rising Parts of dry Land, well known

to all without farther Description. The Waters HYDROGRAPHY, which treats of the divided into watry Parts of the Earth's Surface, divides its Oceans.

Subject as follows, viz. (1.) Oceans; which are those mighty Collections of Water that cover

the greatest Spaces of the Earth's Superficies, and Seas. flow around the Continents. (2.) Seas; thcfe

are finaller Collections of Water, which are en

tirely, or for the greatest part, surrounded by Gulphs. Land. (3.) Gulphs ; which are those Parts of the

Sea that run up into the main Land, and are therewith environ’d, except one Passage whereby

it communicates with the open Sea or Ocean. Streights (4.) Streights; which are those narrow Pafiages

either joining a Gulph to a Sea, or one Part of a Sea or Ocean to another. (5.) Rivers ; which are Streams of fresh Water issuing from Fountains, and gliding in large Chanels through the

Countries to the Sea or Ocean, where they disLakes, embogue themselves. (6.) Lakes are those

small Collections of deep standing Water, entirely surrounded by Land, and having no visible Communication with the Sea.

BEFORE

Rivers.

BEFORE we proceed to treat of the several The Definition Parts of Land and Water above mentioned, it of certain Prewill be necessary to explain the following Pre- cognita, viz. cognita of the Science. (1.) The Axis of the Globe The Axis of is an imaginary Line pasing through the Center the Globe. thereof, about which the Globe is supposed to turn. (2.) The Poles of the Earth or Globe are The Poles. the two Extremities of the Axis, one whereof is call'd the North or Aretic Pole, and the other the South or Antarctic Pole. (3.) The Horizon is that The Horizoz. great Circle which bounds our Sight, and divides the Globe into the visible and invisible Hemispheres. (4.) The Equator is that great Circle The Equator. which divides the Globe into two equal Parts callid the Northern and Southern Hernispheres. (5.) The Meridian is a great Circle passing thro' The Meridian. the two Poles, and divides the Globe equally into the Eastern and Western Hemispheres. (6.) Every great Circle of the Globe is supposed to be divided into 360 equal Parts, which are called Degrees ; and every Degree is divided into Degrees. 60 other equal Parts, callid Minutes. (7.) The Ecliptic is a great Circle representing the Sun's The Ecliptie. annual Path, and is inclined to the Equator in an Angle of 23 Degrees and 30 Minutes, both Northward and Southward. (8.) The Tropics The Tropics. are two leffer Circles which run parallel to the Equator, and touch the Ecliptic on each side ; that on the Nurib is call'd the Tropic of Cancer, and the other on the South the Tropic of Capricorn. (9.) The Polar Circles also run parallel to Polar Circlei. the Equator, and at the same Distance from the Poles, as the Tropics are from the Equator, viz. 23 Degrees and a half. That Circle on the North is calPd the Aretic Circle, and the other on the South the Antarctic Circle. (10.) Latitude is the Latitude. Distance in Degrees from the Equator towards either of the Poles, and measur'd upon the Me

ridian to the North or South; whence ariseth Parallels of North or South Latitude. (11.) Parallels of LatiLatitude. tude are lesser Circles parallel to the Equator and

each other, and are drawn thro' every 5 or 10 Longitude. Degrees of Latitude North and South. (12.) Lon

gitude is the Distance in Degrees from the first

Meridian, and measur'd on the Equator from Zones. Weft to East. (13.) Zones are large Tracts of the

Earth's Surface, lying parallel to the Equator, and encompassing the Globe like broad Belts; whence their Name. Of these there are three

Kinds, viz. the Torrid, Temperate, and Frigid Torrid Zone. Zones. The Torrid Zone is one, and lieth be

tween the two Tropics, and is divided by the Equator ; it hath its Name from the Sun's going

perpendicularly over it, and scorching or terrifying Temperate it with its Heat. The Temperate Zones are two, Zones.

one on each Side the Equator, being included between the Tropics and Polar Circles. In these the

Sun's Heat and the Seasons are temperate. The Frigid Zones. Frigid or Frozen Zones are two also, the North

and the South; they lie between the Polar Circles and the Poles, and encompass the Poles all around. In them the Seasons have the greatest

Extremity of Cold, whence their Name. (14.) Climates. Climates are those Tracts of the Earth's Surface

which run parallel to the Equator, and of such a Breadth from North to South, that the Length of the artificial Day in one surpasseth that in

the next by Half an Hour. Of these Climates Number of there are 24 on each side the Equator, which Climates. reach to the Polar Circles; after which the Cli

mates are reckon'd from the Difference of an entire Month, and are in Number Six; the Sun be ing seen in the first one whole Month without setting; in the second, two Months; in the third, three, and so on, as you see in the Table adjoined.

A TABLE

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