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32. The Tee Joint at Right Angles.—The name commonly applied to two pipes that intersect is "Tee Joint." Some forms of these joints are known in various localities as "Y-Branches" and "Tee Y's." One of the scoops, Fig. 72, was a cylinder cut by a curved plane. A study of Fig. 95 will reveal a similar condition, the branch pipe being cut by the curved surface of the main pipe.

Side Elevation.—The side elevation should be drawn according to the dimensions given in Fig. 96. The profile should be drawn above the side elevation to avoid a confusion of lines. The profile must be divided into sixteen equal parts, and each part numbered, Fig. 96. Extension lines are dropped downward from each division of the profile until they intersect the circumference line of the main pipe. These intersections, A, B, C, etc., are lettered as shown.

Front Elevation.—Extension lines are used to locate properly the front elevation. Fig. 97. A profile is drawn above the front elevation. This profile is divided into as many equal spaces as there are in the profile first drawn. Both profiles must be of the same size since they represent the same pipe. The profile. Fig. 97, should be numbered as shown. It should be noticed that number 1 of the profile of Fig. 96 is at the bottom, while number 1 of the profile of Fig. 97 is on the left-hand side of the horizontal diameter. This is an important fact, and is true of every drawing that has two elevations. Whatever is directly in front in the side elevation appears on the left-hand side in the front elevation. The true shape of the miter line in the front elevation cannot be shown until it is developed. To do this, extension lines are carried over into the front elevation from points A, B, C, etc., of the apparent miter line, Fig. 96. Extension lines are also dropped from each division of the profile in Fig. 97. Starting at point 1 of the side elevation profile, the extension line is traced downward to the apparent miter line, and then horizontally to a correspondingly numbered line dropped from the profile of Fig. 97. This point is marked with a small circle. All other points of the profile of Fig. 96 should be traced in like manner. A curved line drawn through these intersections will give the developed miter line.