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More Places might be quoted, but these are fufficient ; for the holy Scriptures were not given us to philosophize by, but to increase our Piety. 2. Some Places of Scripture are also produced, which do not speak of the Mobility of the Earth, but of it's Stability and Permanency ; as that in Job aforesaid (s),
THUS we have declared in brief what that Motion is, which the Copernicans assign to the Earth; the more full and accurate Explication of which belongs to Astronomy, And this Motion being supposed, all the Phænomena we observe in a Globe revolved about it's Axis, must be applied to the Earth, viz. That the Axis upon which it is turned, is one of the Diameters: That the Poles are two immoveable Points in the Extremities of the Axis : That the great Circle, or Perimeter, in which the Rotation is made, is the Equator with it's Parallels, &c.
LET us now consider the Velocity of the Earth's Motion; which, in that about it's Axis, is not over all the Earth equal, but different according to the Distance from the Equator ; being there
brim to the other, round all hended to be 25031,4 Miles, about, and a line of thirty cu- which, divided into 24 Hours, bits did compass it round about. makes the Revolution to be But as 7:22 :: 10:31} Cu. at the Rate of about 1043 bits is very near the true Length Miles in an Hour; a Rotation of the Line that ought to en- that would as easily throw off compass a round Vessel of ten the Parts of the Earth, espeCubits Diameter.
cially the Waters, as the whirl. (8) Such as Pfal. xciii. 1. ing round of a Wheel, or a cxix. 9o. civ. 5. Ecclef. i. 4. Globe, would the loose Dus and i Chron. xyi. 30. which and Water thereon ; but by Texts are all understood by Reason the Gravitating Powersal learned Commentators to mean exceeds the Centrifugal, as the unalterable Condition, Se. 2174 exceeds 7,54,064, that curity, Peace, and Tranquility, is, above 288 times ; there. of the Earth. .
fore all Parts lie quiet and le· The Ambit of the Earth, cure in their respective Places. by the most accurate, is appre- Perbam's Afro-Theol. p. 149.
swiftest as passing thro' a greater Space, and so by Degrees Nower towards the Poles, as passing thro a less Space in the same Time. Therefore since every Part of the Earth is moved thro' the Space of it's Periphery (or 360 Degr.) in 24 Hours; the Space of one Hour's Motion is found by dividing 360 by 24, which gives in the Quotient 15 Degr. and so much doth any Place on the Earth move (whether in the Equator or without it) in an Hour. Also 15 Degr. in the Equator make 125 German Miles, therefore it revolves 15 such Miles (or one Degr.) in 4 min. and in one min. 3} Miles.
BUT Places without the Equator, lying towards either Pole, are in the same Time revolved the same Number of Degrees : but these Degrees are much less than those in the Equator; so that the Celerity of Motion, or Progression, is as the Sines of the Arches by which these Places are distant from the Pole. Example. The Distance from the Equator (or Elevation of the Pole) of Amsterdam is 52 degr. 23 min. therefore the Di. stance from the Pole (or Complement of Latitude) is 37 degr. 37 min, whose Sine is 61037. Suppose another Place, under the Equinoctial, diftant from the Pole go Degr. whose Sine alfo is 100000, but the Place under the Equinoctial moves 15 Miles in 4 min. and 225 an Hour. Therefore by the Golden Rule, as 100000 : 61037: ; 15:9 Miles, or so is 225 to 137 Miles, So that Amsterdam is carried every Hour 137 Miles, and in 4 min. 9 Miles, by this Motion.
THIS is more easily found by the foregoing Table; for by dividing 360 by 24 we find each Place to move 15 Degr. of it's own Circle in an Hour, and therefore i Degr. in 4 min. &c. confulting the Table with the Latitude of the Place, we find how many Miles it moves in 4 min. For
Example ; The Latitude of Stockholm is about 60 Degr. opposite to which in the Table is 71 Miles, Therefore Stockholm revolves so many Miles in 4 min. and such is the first Motion in divers Places..
THE Second Motion of the Earth, is it's Change of Place; whereby every Part of it moves the same Space with the same Velocity. This Motion is determined by the Distance of the Earth from the Sun, or the Semidiameter of the Orbit in which it performs it's annual Revolution, moving in a Day about a Degr. and in an Hour 21 min.
As to the third Motion of the Earth, because it is more difficult to conceive, we shall leave it to Astronomers, who have found it necessary to be supposed. Origanus moves a Doubt about the second Motion, and supposes the Earth to be only moved by the first, but the Sun and fixed Stars by the second : Tho' the above-cited Appearances, in the Motions of the Planets, sufficiently confirm this annual Motion (b),
(b) This imaginary third and the Regress of the Nodes; Motion of the Earth they were from which Thing nevertheless obliged to suppose, to account no Variation of Declination, profor the disputed Inequality of perly so called, can arise. Whithe Declination of the Ecliptic, ston's Aftron. Lect. pag. 57. which is now by most Astro- That there is such a Nutation nomers thought to be always whereby the Axis of the Earth the same; seeing there is no doth twice incline towards the thing which mould disturb the Ecliptic, and twice return to perpetual Parallelism of the ic's former Position, see in Earth, on which this Equality Newton's Prin. Phil. Nat. Booke depends, except it pould be the üi. Prop. 21. in sensible Nutation of the Axis,
CH A P.
C H A P. VI. Of the Situation, or Place, of the Earth, in Res
spect of the Planets and fixed Stars.
H E Situation of the Earth, in the System of
| the World, in respect to the rest of the Pla. nets, hath some Relation to the Account we gave of the Earth's Motion, in the preceeding Chapter. For it is the general Opinion of the Ptolemaic Astronomers and Philosophers, that the Earth, being the Center of the World, is placed in the middle of the Stars and Planets (a): But the Copernicans, with the antient Pythagoreans, place the Sun in the Center of all the Stars, and make the Earth a.Planet performing an annual Revolution about him, between Mars and Venus ; as is best understood by a Diagram of the System. Nevertheless they both agree in this, that the Earth may be accounted the apparent Center of the diurnal Motion, by which the Stars seem to be carried about in twenty four Hours. For both Astronomy and Geography require this Supposition; so that whether we adhere to the Ptolemaic or Copernican Hypothesis, we do not detract from the Certainty of general Astronomy or Geography. Because the Difference of these Opinions consists only in this ; that the Ptolemaics will have this Motion to
(a) Since the World, or Uni- by the World here is only our verse, is infinite, the central Solar System, in which Sense Place of it cannot be determi- he must be taken in what folned: What our Author means lows,
be be in the Stars themselves, but the Pythagoreans in the Earth; the Stars in the mean time refting : neither of which need be determined in Geography or common Astronomy.
ACCORDING to the Ptolemaics the Situation of the Earth, in respect of the Planets and fixed Stars, is this ; The Earth in the Center, then the Moon, Mercury, Venus, The Sun, Mars, Jupiter, Saturn, and the Fixed Stars.
ACCORDING to the Copernicans ; The Sun is placed in the Center of the System, as the Heart and Focus of the World ; and next him is the Orbit of Mercury, then that of Venus, the Earth, with the Moon, Mars, Jupiter, Saturn, and the Fixed Stars.
IF it be required how far distant we are from each of the Planets, we must know that the Distance is not always the same, but continually changing; and therefore Aftronomers reckon three Degrees of Distance, viz. the least, greatest, and mean or middle Distance; which last of the Earth, from the rest of the Planets, is as follows, accor, ding to most Astronomers (6).
f The Moon 5 01
of it's SemiThe Sundistant from
asso ? diameters,
NEVERTHELESS the Distance of the Earth from Mars, Jupiter, Saturn, and the fixed
(6) See Note (m) at the end of this Chapter.