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Place, and is moved by a Handle E, which is called 
the Meridian Handle, and has a Nonius Index di- 
vided into every three Minutes. 
Above this Meridian Semicircle is fatten'd a circu- 
lar Plate, upon which are affixed two other circular 
Plates FF, moveable the one upon the other, and arc 
called the Equatorial Plates ; one of them, reprefent- 
ing the Plane of the Equator, is divided into twice 
12 Hours, and thefe are fubdivided into every io 
Minutes of Time. This Plate is moved by a Handle 
G, called the Equatorial Handle, and has a Nonius 
Index for fhewing every Minute. 
Above this Equatorial Plate there is a Semicircle 
HH, which is called the Declination-Semicircle, as 
reprefenting the Half of a Circle of Declination, or 
horary Circle, and is divided into twice 90°, being 
moved by the Handle K, which is called the Declina- 
tion-Handle. It has alfo a Nonius Index for fubdi- 
viding into every three Minutes. 
Above this Declination -Semicircle is fattened a 
Refk&ing Telefcope LL, of the Gregorian Con- 
ftru&ion, the focal Length of its great Speculum be- 
ing 18 Inches. 
In order to adjuft the Inftrument for Obfervation, 
the ttrtt thing to be done, is to make the Horizontal 
Plates level or horizontal, by means of the two Spi- 
rit-Levels, and the four Screws in the Crofs-Pedcftal. 
This being done, you move the Meridian Semicircle, 
by means of the Meridian Handle, fo as to raife the 
Equatorial Plates to the Elevation of the Equator of 
the Place ; which is equal to the Complement of the 
Latitude (and which, if not known, may likewife 
be found by this Inttrument, as (hall be afterwards 
H h 2 (hewn). 
