Pen. F Pencil, larger sort would be found inconvenient. Thehead of the bow compass is so constructed thatit will roll round with great ease between thefingers, g is the trammel, an instrument con-sisting of two rulers fixed at right angles to eachother, with a groove in each. A rod witli… … —Let the distance of the first pin at b fromthe pencil at a, be equal to half the shortestaxis, and the distance of the second pin at cfrom A, to half the longest axis; the pins beingput in the grooves, move the pencil at a, whichwill describe the ellipsis, h is a hair compass,with two steel…
Design · Decoration and ornament · Art
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