The works of Edmund Gunter : containing the description and use of the sector, cross-staff, bow, quadrant, and other instruments : with a canon of artificial sines and tangents to a radius of 10.00000 parts, and the logarithms from an unite to 10000 : the uses whereof are illustrated in the practice of arithmetick, geometry, astronomy, navigation, dialling, and fortifcation : and some questions in navigation added by Mr. Henry Bond ... : to which is added, the description and use of another sector and quadrant, both of them invented by Mr. Sam. Foster ..., furnished with more lines, and differing from those of Mr. Gunters both in form and manner of working. -- (1673)
Gunter, Edmund, 1581-1626 · London : Printed by A.C. for Francis Eglesfield ... · leaf 77
- ~ The general Ufe of Sines and Tangentss ~ ig 20 and 20 hall bea Chord of 40, and the Diftance between 30 and 305 _ fhall be a Chord of 69, and fo in the reft, 2. BecaufeaSine is the half of the Chord of the double Ark, the Pro- portion holdeth. | eae : a … As the Diameter F H untorhe Radius A H, fo che Chord BE unto -the Sine D E, or the Chord G L untothe Sine A L, and then if the Ra- - dius A Hbe put for the Diameter, whichis a Chord of 180 gr. the Sine D Eor AL, fhall ferve fora Chord of 80 gr. and che Semiradius which is he Sine-of 3ogr. thall…
Mathematical instruments · Logarithms · Sundials · Navigation -- Early works to 1800
Internet Archive · Fisher - University of Toronto · Public domain (published before 1931). Free to use for anything.
