. A textbook on mechanical and electrical engineering . describethe circle the two diameters A Eand G C 2lX. right angles to eachother. Bisect one of the fourequal arcs, as A G at H, and ^ draw the diameter HOD. Bi-sect another of the equal arcs,as A C at B, and draw thediameter EOF. Straight linesdrawn from A to B^ from Bto C, etc. will form the re-quired octagon. Problem Is.—To irLscii1>e a regxQar polygon of anynuBiber of sides in a given, circle. CoxsTRUCTiON-.—In Fig. 51, from (9 as a center, with thedividers set to If, describe the cir-cle ^ 7 CD. Draw the two diam-eters
. A textbook on mechanical and electrical engineering . describethe circle the two diameters A Eand G C 2lX. right angles to eachother. Bisect one of the fourequal arcs, as A G at H, and ^ draw the diameter HOD. Bi-sect another of the equal arcs,as A C at B, and draw thediameter EOF. Straight linesdrawn from A to B^ from Bto C, etc. will form the re-quired octagon. Problem Is.—To irLscii1>e a regxQar polygon of anynuBiber of sides in a given, circle. CoxsTRUCTiON-.—In Fig. 51, from (9 as a center, with thedividers set to If, describe the cir-cle ^ 7 CD. Draw the two diam-eters D 7 and A C at right anglesto each other. Divide the diam-eter D 7 into as many equal partsas the poh-gon has sides (in thiscase seven). Prolong the diam-eter A C and make 3A equal tothree-fourths of the radius -5 and 2^ the second di-vision from D on the diameter D 7,draw the line 31, cutting the cir-cumference at /. Draw thechord D /, and it is one side of the required may be spaced off around the circumference. Fi-:. The § 13 GEOMETRICAL DRAWING 41
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmechani, bookyear1902
