Hatfield, Robert Griffith, 1815-1879. [from old catalog] · New York & London, Wiley and Putnam · leaf 63
122.—To draw a tangent to an ellipsis. Let abed, {Fig:88,) be the given ellipsis, and d the point of contact. Find thefoci, {Art. 115,)/and/, and from them, through d, draw/e andf d; bisect the angle, {Art. 77,) e d o, with the line, sr; then5 r will be the tangent required. … c Fig. 89. 123.—An ellipsis with a tangent given, to detect the pointof contact, hetagbf, {Fig. 89,) be the given ellipsis and tan-gent. Through the centre, e, draw a b, parallel to the tangent;any where between e and/, draw c d, parallel to ab ; bisect cd in0 ; through o and e, drsLW f g ; then g…
Carpentry · Architecture
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![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-118-325.webp)
