Copy 2

The description and use of ... Gunter's quadrant ... To which is added, the use of Nepiar's [sic] bones in multiplication, division, and extraction of roots ... / [William Leybourn].

Leybourn, William, 1626-1716

Date:: 1731-1732

Credit: The description and use of ... Gunter's quadrant ... To which is added, the use of Nepiar's [sic] bones in multiplication, division, and extraction of roots ... / [William Leybourn]. Source: Wellcome Collection.

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$calld GUNTER’s Quadrant. 4% 6. If ftanding upon a known Alti-. tude, and you would thereby know the - Diftance, work as you did before; on- ly that which was then the Parts of Right Shadow, muft now be the Parts of Contrary Shadow; and that which _ was then the Parts of Contrary Shadow, muft now be the Parts of em Shadow. BES 26 G5 ANS BES ABS 28s age aay age a0 BAR age abe aR ate ok HG: GS B24 99s 305 ate BRS a 28s 086 S:e:.c tr - & The Defeription and Ufe of the Notiurnal, which is ufually put upon the Back{i de se Gunter’s Quadrant. TS an Inftrument fitted chiefly to know the Hour of the Night by © the Stars: It confifts of two Parts, the Fixed andthe Moveable. Fhe fixed Part, being the outermoft Circle, is divided in- to 24 ( Parts sreprefenting theHours of the Night ; of which fo many as are necef- fary are inferted, which arefrom 4 in the Afternoon till 8 in the Morning : Each Hour is divided into Halves, Quarters, and Half. iss lad and far- ther,$