Path of the Moon, 223–226.

Of Jupiter's moons, 228.

Pendulums, their vibrating slower at the equator than near

the poles proves that the Earth turns on its axis, 82.
Penumbra what, 305.

Its velocity on the Earth in solar eclipses, 307.
Period of Eclipses, 268, 282.

Phases of the Moon, 213.

Planets, much of the same nature with the Earth, 35.

Some have Moons belonging to them, 35.

Move all the same way as seen from the Sun, but not as
scen from one another, 37.

Their moons denote them to be inhabited, 66.

Planets the proportional breadth of the Sun's disc, as seen
from each of them, 67.

Their proportional bulks as seen from the Sun, 67.
An idea of their distances from the Sun, 68.

Appear bigger and less by turns, and why, 68.

Are kept in their orbits by the power of gravity, 74, 107

-112.

Their motions very irregular as seen from the Earth, 97.
The apparent motions of Mercury and Venus delineated
by pencils in an Orrery, 98.

Elongations of all the rest as seen from Saturn, 105.
Describe equal areas in equal times, 109.

The eccentricities of their orbits, 110.

In what times they would fell to the Sun by the power
of gravity, 111.

Disturb one another's motions, the consequence of it, 115.
Appear dimmer when seen through telescopes than by
the bare eye, the reason of this, 119.

Planetary globe described, 449.

Polar circles, 140.

Poles of the planets, what, 38.

Of the world, what, 86.

Celestial, seem to keep in the same points of the heavens
all the year, and why, 138.

Precession of the Equinoxes, 181-186.

Projectile force, 107; if doubled, would require a quadruple
power of gravity to retain the planets in their orbits,

109.

Is evidently an impulse from the hand of the ALMIGHTY,

114.

Ptolemean system absurd, 71, 100:

R.

Rays of light, when not disturbed, move in straight lines,
and hinder not one another's motions, 117.

Are refracted in passing through different mediums, 119.
Reflection of the atmosphere, causes the twilight, 123.
Refraction of the atmosphere bends the rays of light from
straight lines, and keeps the Sun and Moon longer in
sight than they would otherwise be, 124.

A surprising instance of this, 1 7.

Must be allowed for in taking the altitudes of the celes
tial bodies, 127.

Satellites, the times of their revolutions round their prima-
ry planets, 51, 58, 61.

Their orbits compared with each other, with the orbits
of the primary planets, and with the Sun's circumfer-

ence, 231.

What sort of curves they describe, 231.

Saturn, with his ring and moons, their phenomena, 60-62.
The Sun's light 1000 times as strong to Saturn as the
light of the full Moon is to us, 64.

The Phenomena of his ring farther explained, 149.
Our blessed SAVIOUR, the darkness at his crucifixion super-
natural, 317.

The prophetic year of his crucifixion found to agree with
an astronomical calculation, 416.

Seasons, different, illustrated by an easy experiment, 141;
by a figure, 145.

Shadow, what, 261.

Sidereal time, what, 160; the number of sidereal days in
a year exceeds the number of solar days by one, and
why, 164.

An easy method for regulating clocks and watches by it,

164.

SMITH (Rev. Dr.) his comparison between moon-light and
day-light, 64.

His demonstration that light decreases as the square of
the distance from the luminous body increases, 118.
(Mr. GEORGE) his Dissertation on the progress of a solar
eclipse; following the tables at 276.

Solar astronomer, the judgment he might be supposed to
make concerning the planets and stars, 95, 96.

Sphere, parallel, oblique, and right, 93.

Its circles, 140.

Spring and neap tides, 253.

Stars, their vast distance from the Earth, 32, 138.

Probably not all at the same distance, 32.

Shine by their own light, and are therefore Suns, 33;

probably to other worlds, 33.

A proof that they do not move round the Earth, 78.
Have an apparent slow motion round the poles of the
ecliptic, and why, 186.

A catalogue of them, 382.
Cloudy, $84.

New, 385.

Some of them change their places, 386.

Starry heavens have the same appearance from any part of
the solar system, 94.

SUN, appears bigger than the stars, and why, 33.

Turns round his axis, 37.

His proportional breadth as seen from the different plan-
ets, 67.

Describes unequal arcs above and below the horizon at
different times, and why, 92.

His centre the only place from which the true motions of
the planets could be seen, 95.

Is for half a year together visible at each pole in its turn,
and as long invisible, 141, 246.

Is nearer the Earth in winter than in summer, 151..
Why his motion agrees so seldom with the motion of a
well-regulated clock, 165-181.

Would more than fill the Moon's orbit, 231.

Proved to be much bigger than the Earth, and the Earth
to be bigger than the Moon, 262.

Systems, the solar, 37-71; the Ptolemean, 71; the Ty-
chonic, 72.

T.

Table of the periods, revolutions, magnitudes, distances, &c.
of the planets, 73.

Of the air's rarity, compression, and expansion, at differ-
ent heights, 122.

Of refractions, 126.

For converting time into motion, and the reverse, 159.
For shewing how much of the celestial equator passes
over the meridian in any part of a mean solar day;

and how much the stars accelerate upon the mean solar
time for a month, 163.

Table of the first part of the equation of time, 171; of the
second part, 178.

Of the precession of the equinoxes, 183.

Of the length of sidereal, Julian, and tropical years, 189.
Of the Sun's place and anomaly, 190—192.

Of the equation of natural days, 194–205.

Of the equation of time, 208-216.

Of the conjunctions of the hour and minute hands of a
watch, 222.

Of the curves described by the satellites, 232.

Of the difference of time in the Moon's rising and setting
on the parallel of London every day during her course
round the ecliptic, 236.

Of the returns of a solar eclipse, 272, 275.

Of eclipses, 285-302.

For calculating new and full Moons, and eclipses, 329-
346.

Of the constellations and number of stars, 382, 383.

Of the Jewish, Egyptian, Arabic, and Grecian months,
392-394.

For inserting the Golden numbers right in the calendar,
397.

Of the times of all the new Moons, for 76 years, 403—
411.

Of remarkable æras or events, 422, 423.

Of the Golden number, Number of Direction, Dominical
letter, and days of the months, 424-429.

THALES'S eclipse, 279.

THUCYDIDES's eclipse, 281.

Tides, their cause and phenomena, 249-260.

Tide-Dial described, 454.

Trajectorium Lunare described, 452.

Universe, the work of Almighty Power, 32, 114.
Up and down, only relative terms, 86.

Upper or under side of the Earth, no such thing, 87.

ง.

Velocity of Light compared with the velocity of the Earth in
its annual orbit, 139.

Venus, her bulk, distance, period, length of days and nights,

41.

Is our morning and evening star, 42.
Her axis, how situate, 43.

Her surprising phenomena, 43-47.

The inclination of her orbit, 48.

When she will be seen on the Sun, 48.

How it may probably be soon known if she has a satel
lite, 48.

Appears in all the shapes of the Moon, 40, 101.

An experiment to shew her phases and apparent motion,

101.

Vision, how caused, 117.

W.

Weather, not hottest when then Sun is nearest to us, and
why, 151.

Weight, the cause of it, 86.

World, not eternal, 116.

Y.

Wear, Tropical, Sidereal, Lunar, Civil, 389; Bissextile,
Roman, 390; Jewish, Egyptian, Arabic, and Grecian,
391, 394; how long it would be if the Sun moved
round the Earth, 78.

Zodiac, what, 381.

Z.

How divided by the ancients, 381.

Zones, what, 141.