The svrveyor in foure bookes / By Aaron Rathborne.

  • Aaron Rathborne
Date:
1616
Catalogue details

Licence: Public Domain Mark

Credit: The svrveyor in foure bookes / By Aaron Rathborne. Source: Wellcome Collection.

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    — Derins XLIL T he quantitie or meafure of an angle, is the arch of a circle, deferibed | from the point of the fame angle , and intercepted betweene the : two fides of that angle, A. Sinthe Triangle A.B. C. the mea- . }, fure or quantitie of the angle B.A. x “Cc. isthe arch B.D. or E. F. for the r= 4 a circumference of enerie circle ( whether eel greater, or leffer) is dinided into 360 e- ae 2 - quall parts, which are called degrees, and / ne a Ny a cuerie degree into 60 fcruples or minutes, ($s p / and cuerie minute into fo manie feconds, | &c. Which parts or degrees are greater or jeffer, as the circles, whofe parts they are, are greater or leffer; and thofe ar- a hf ches which containe the fame number of parts or degrees in equall circles, 64 are equall; and in vnequall circles, they are called like arches ; as the arches B. D.and H.G.are equall ; but. the arches B. D. and E. FE. are like arches: for as B.D. is 50 degrees in the greater circle, fois E. F. 50 degrees in the lefler circle. And the like of others. Pro 3.8. = > So tees ~ Derin, XLITI, The Quadrant of a circle is the fourth part. thereof, or an arch con- taining gO degrees. S the arch K. B. D. in the former Semicircle is a Quadrant of that whole circle, or a fourth part thereof, and containeth go degrees. DEFIN, XCD The Complement of an arch, leffe thena Quadrant , is fo much asthat | arch swanteth of 9O degrees. | i i AS the Complement of the arch B. D. 50 degrees in the former Semi- circle, is the arch K.B. 40 degrees. DzeBiny, XLV. ~ oe } The Exceffe of an arch, greater then a Quadrant ,is fomuch asthefaid | | arch is more then 90. degrees, AS the Excefle of thearch H.K.B. D. 130. degrees, isthe arch H.K. 40 1} degrees more then aQuadrant, that is more then K.D. DEFEIN.
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