The American builder's companion : or, A system of architecture, particularly adapted to the present style of building ; illustrated with seventy copperplate engravings . Z FIG. 13, 14, and 15. rpi . , •?--• lu, ,.*, una ID. sides whatever. On the extreme of the given side make a semieirele of 10 AMERICAN BUILDERS COMPANION. any radius, it will be most convenient to make it equal to the side of the polygon;then divide the semicircle into the same number of equal parts as you would havesides in the polygon, and draw the lines from the centre through the severalequal divisions in the semicircle,
The American builder's companion : or, A system of architecture, particularly adapted to the present style of building ; illustrated with seventy copperplate engravings . Z FIG. 13, 14, and 15. rpi . , •?--• lu, ,.*, una ID. sides whatever. On the extreme of the given side make a semieirele of 10 AMERICAN BUILDERS COMPANION. any radius, it will be most convenient to make it equal to the side of the polygon;then divide the semicircle into the same number of equal parts as you would havesides in the polygon, and draw the lines from the centre through the severalequal divisions in the semicircle, always omitting the two last, and run the givenside round each way upon those lines ; join each side, and it will be completed. «FIG. to describe a pentagon. Let a 6, be the given side, and continue it outto e; on a the centre, describe a semicircle ; divide it into five equal parts ;through 2, 3, and 4, draw « 2, a c, a b, make 5 b, equal to a 6, 2 c, and c b, eachequal to « 5, or a 2 ; join a 2, 2 c, c b, and b 5; in the same way may any poly-gon be drawn, only divide the semicircle into the same number of parts that thepolygon is to have A-l^f njarnin. \^er. AMERICAN BUILDERS COMPANION. li PLATE III. FIG. make an octagon in a square. Find the centre n, with the distance, a n,and in the points a, b, c, d, make the arches e n m, I n h, i n f, and k n g; join I &,m ?, // g, andfe, which completes the octagon. FIG. three hnes being given to make a triangle. Take one of the given sides,a b, and make it the base of the triangle ; take the second side, ca, in your com-passes, place one foot in a, and make the arch at c ; take the third side, b c, andplace one foot of the compasses in b, and make the intersection c, then draw c a,and c b, which completes the triangle. FIG. right lines being given to find a mean proportion. Join at; and c b, inone straight line ; divide it into two equal parts at the point n, with>the radius n«,or n b
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Keywords: ., bookautho, bookcentury1800, booksubjectarchitecture, bookyear1827
