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THE

Description and Use

OF THE

GLOBES,

AND THE

CORRER 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 Inftrument-Maker, at the Orrery and Globe near Salisbury-Court; and RICHARD CUSHEE, GlobeMaker, at the Globe and Sun between St. Dunstan's Church and Chancery-Lane; both in Fleet-ftreet.

M.DCC.XXXII.

ADVERTISEMENT.

MR

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 ufeful 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 Instruments ready made by him; as Cafes for Drawing, Surveying Inftruments, Sun-Dials, Weather-Glaffes, &c.

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PROB. X. The Hour of the Day at one Place, being

given to find the correspondent Hour (or what

o'Clock it is at that Time) in any otber Place. 96

PROB. XI. The Day of the Month being given, to

find thofe Places on the Globe where the Sun will be

Vertical, or in the Zenith, that Day.

PROB. XII. A Place being given in the Torrid Zone,

to find thofe two Days in which the Sun fhall be

Vertical to the fame.
98

PROB. XIII. To find where the Sun is Vertical at any

given Time affigned; or, the Day of the Month

and the Hour at any Place (fuppofe London) being

given, to find in what Place the Sun is Vertical at

that very Time.

PROB. XIV. The Day, and the Hour of the Day at

one Place, being given; to find all thofe Places

upon the Earth, where the Sun is then Rifing,

Setting, Culminating, (or on the Meridian ;) alfo

where it is Day-Light, Twilight, Dark-Night,

Mid-Night; where the Twilight then begins, and

where it ends: the Height of the Sun in any Part

of the illuminated Hemisphere; alfo his Depression

in the obfcure Hemisphere.

PROB. XV. The Day of the Month being given to

Shew, at one view, the Length of Day and Night

in all Places upon the Earth at that Time; and

to explain how the Viciffitudes of Day and Night

are really made by the Motion of the Earth round

her Axis in 24 Hours, the Sun ftanding fill. 100

PROB. XVI. To explain in general the Alteration of

Seafons, or Length of the Days and Nights, made

in all Places of the World, by the Sun's (or the

Earth's) annual Motion in the Ecliptick.

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