In Fig. 368, A B D C shows the elevation and N P O R the plan of a vessel having straight sides and semicircular ends, one end of which is slanting. First draw a correct plan and elevation of the article, seeing that each point of the elevation is carefully projected from its corresponding point in the plan. Divide half of the boundary line of the top into any number of equal spaces, commencing at O, all as shown by the small figures 1, 2, 3, etc., in the plan. From the points thus obtained carry lines vertically until they cut the top of the elevation, as shown in the points between B and L; also continue the lines downward until they meet the line T O, all as shown. From the points between L and B thus obtained draw lines parallel to B D, producing them upward indefinitely, and continue them downward until they meet the bottom line of the elevation F D, as shown. At right angles to the lines thus drawn, and at any convenient distance from the elevation, draw G H. With the dividers, set off from the line G H, on each of the lines drawn through it, the distance from T O, on the lines of corresponding number, to the curved line PO. In other words, make G K equal to T 6 of the plan. Set off spaces on the other lines corresponding to the distance on like lines in the plan. Through the points thus obtained trace a line, as shown by K H. Then G H K will be the half profile of the end of the vessel on any line, as L M, drawn at right angles to the line D B. The stretchout of the pattern is to be taken from the profile thus constructed. At right angles to D H, and at any convenient distance from it, draw U V, upon which lay off twice the stretchout of K H, numbering each way from the central point 1, as shown. From the points in the stretchout thus obtained draw measuring lines at right angles to it indefinitely. With the blade of the T-square set at right angles with D B, and brought successively against the points in F D, cut lines of corresponding number drawn through the stretchout. Then a line traced through the points of intersection, as shown by Y Z, will be the pattern of the bottom end of the piece. In like manner bring the blade of the T-square against the points in L B and cut corresponding measuring lines, as shown, for the top of the pattern. If it is desired to make a joint upon the line E F of the elevation, the triangular shaped piece ELF may be added to the pattern as follows: With the dividers take the distance E F of the elevation as radius, and from the point Z of the pattern as center describe an arc. In like manner, with E L of the elevation as radius, and point R in the upper line of the pattern as center, describe a second arc, cutting the first arc in the point W. Connect W with R and also with Z. The triangular piece at the opposite end terminating in point X is added in a similar manner, thus completing the entire pattern of that portion of the vessel from the line E F to the right.
Fig. S68. - Pattern of the Flaring End of an Oblong Tub.