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A simple line drawing, like that shown in Fig. 161, illustrates all that is contained in Fig. 159.

Hexagonal make a hexagon, in Fig. 162, take 6 and 15-16 on the tongue and 12 inches on the blade, and apply as shown on a base line which forms a square around the figure.

The side of a hexagon equals the radius of the circumscribing circle. The square width is de termined from two parallel sides a diagonal of the figure is a line from opposite angles.

The first pair of hips are set up as in an octag onal roof. The second and third pairs have a side bevel. To find this, take half the side of the hexagon on the tongue, and half the square width added to the gain of the hip rafter in running that distance, on the blade. The tongue gives the cut. Strike the bevel across the rafter. Now, the second and third pairs are to be measured back shorter than the first pair, on their middle lines, just half the length of this bevel. The third pair has the bevel cut on both sides from the center. The backing of the hips is found by taking 7-12, the rise of the roof, on tongue, and the length of hip on blade; the latter gives the cut. The side of the hexagon is 7-12 its square

width, or apothem. The lengths and bevels of the jack rafters are found as in octagonal roofs.

To Timber a Hexagonal Roof.—On the linel-2, Fig. 163, is the seat of the hips, 3-4 will be the rise. On the line 1-S, say at 0, draw a line at right angles touching the line 1-2, which is the seat of a jack rafter. From 0-P at right angles draw P-E equal to P-F, and connect OH; this gives the bevels and length for plumb cut of jack rafter. From 6-7 draw the line 8-9 indefinitely; set the compasses to 1-4, which is the length of the hip, and this length at 6 intersects 9-8 at 8; repeat from 7, which is the covering for one side of the roof, the intermediate lines being the lengths of jack rafters and bevels for side cut. On the line 1-2, say at B, take B for a center, touching the line 4-2, for radius, describe the arc BC, through B, at right angles to 1-2, draw the line DE, and from C to E and C to D will be found for backing the hips.