Crossword-Solution: DODECAGON 9 letters, 1 clue 🏆 scrabble score: 14

You are acquainted, of course, with the modern rule of giving the bastions a salient angle of fifteen degrees in excess of half the angle of the figure in all figures from the square up to the dodecagon? Well, Fort Amitie being a square--or rather a right-angled quadrilateral--the half of its angle will be forty-five degrees; add fifteen, and we get sixty; which is as nearly as possible the salience of our flanking towers; only they happen to be round.

Book I of the _Metrica_ calculates the areas of triangles, quadrilaterals, the regular polygons up to the dodecagon (the areas even of the heptagon, enneagon, and hendecagon are approximately evaluated), the circle and a segment of it, the ellipse, a parabolic segment, and the surfaces of a cylinder, a right cone, a sphere and a segment thereof.

You may do this: you may put the word _hexagon_ or _dodecagon_, or any other word describing a polygon in the place of _Circle_ in your proof, and the proof would be just as good as before.

Antiphon divided the circle into four equal arcs, and by joining the points of division obtained a square; he then divided each arc again into two equal parts and thus obtained an inscribed octagon; thence he constructed an inscribed dodecagon, and perceived that the figure so inscribed more and more approached the shape of a circle.

FROM A CENTRE INSCRIBE A STARRED DODECAGON ANALOGOUS TO NUMBER 65.] [Illustration: 67 TRIANGULAR PLAN.