The GREAT ORRE

ORREent forts

Four Feet in Diameter Made in THO: WRIGHT Mathematical Inft ment-maker TO HIS MAJESTY

THE

Description and Use

OF THE

GLOBES,

AND THE

ORRER Y.

To which is prefixed,

By way of INTRODUCTION, a

Brief Account of the SOLAR SYSTEM.

By JOSEPH HARRIS.

The SECOND EDITION.

LONDON:

Printed for THOMAS WRIGHT, Mathematical In-
ftrument-Maker, at the Orrery and Globe near Satis-
bury-Court; and RICHARD CUSHEE, Globe-
Maker, at the Globe and Sun between St. Dunstan's
Church and Chancery-Lane; both in Fleet-street.

M.DCC.XXXII.

ADVERTISEMENT.

R. WRIGHT has lately made feveral very large ORRERYS, with all the Motions of the primary and fecondary PLANETS, which makes the Price very great: But being willing that Academies, Schools, &c. fhould have the Benefit of this useful Machine, he has contrived an ORRERY, which exhibits what relates to the Motions of the Sun, Earth and Moon; to be fold at a very moderate Price.

He also has great Choice of Mathematical Inftruments ready made by him; as Cafes for Drawing, Surveying Inftruments, Sun-Dials, Weather-Glaffes, &c.

2-28-47 APE

THE

2-27-47

56903

CONTENTS.

The INTRODUCTION: Containing

brief Account of the Solar System, and

of the fixed Stars.

SECT. I.

OF

F the Order, and Periods of the Pri-

mary Planets revolving about the Sun;

and of the Secondary Planets round their re-

Spective Primaries.

Of the Primary Planets.

-Of the Secondary Planets.

Pag. I

4

-Of the Annual and Diurnal Motion of the Pla-

nets.

6

7

That the Planets are Opaque and Globular.

-That the Earth is placed betwixt the Orbits of

Mars and Venus.

8

ibid.

-That the Planets turn round the Sun.

-That the Earth also turns round the Sun. 12

-How the Annual and Diurnal Motions of the

Planets are computed.

13

How the Relative Distances of the Planets from

the Sun are determined.

15

How their abfolute Distances from the Sun are

computed.

19

-How the Magnitudes of the Planets are deter-

mined.

22

-Why the Moon appears bigger than any of the

Planets.

A Table of the Distances, Magnitudes, Periodical

and Diurnal Revolutions of the Planets.

-Of Comets.

SECT. II. Of the fixed Stars.

23

24

25

27

That the fixed Stars are luminous Bodies, at im-

menfe Distances from us.

-Of Telescopical Stars.

The Stars digefted into Conftellations,

Of the Galaxy, or Milky Way.