Hatfield, Robert Griffith, 1815-1879. [from old catalog] · New York & London, Wiley and Putnam · leaf 42
Fig. 50. 90.— To describe a circle within any given triangle, so thatthe sides of the triangle shall be tangical. Let a b c, {Fig.50,) be the given triangle. Bisect the angles, a and 6, accordingto Art. 77; upon d, the point of intersection of the bisectinglines, with the radius, d e, describe the… … Fig. 51. 91.—About a given circle^ to describe an equi-lateral tri-angle. Let a d b c, {Fig. 5],) be the given circle. Draw thediameter, c d ; upon d, with the radius of the given circle, de-scribe the arc, a e b ; join a and b ; drsiwfg, at right angles tod c ; make/c and c g, each equal to a b ;…
Carpentry · Architecture
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![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-150-84.webp)
![An illustration from Divina proportione : opera a tutti glingegni perspicaci e curiosi necessaria oue ciascun studioso di philosophia: prospettiua pictura sculptura: architectura: musica: e altre mathematice: suavissima: sotile: e admirabile doctrina consequira: e delecterassi: co[n] varie questione de secretissima scientia (1509)](https://img.insideoutlibrary.com/img/200/ia-divinaproportion00paci-134-367.webp)
