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Rh are made with extra high legs, and the connection from riser isas shown in Figure 33. In another case, in a 14-story building, an offset was made in each riser over the windows of the seventh floor, the upper part running on the opposite side of the tier of windows from the lower part, the spring of the pipe in this offset taking care of the expansion at this, point. The risers were anchored rigidly in the center of each section. Arrangements of this kind are frequently used, and the chief objection is that unless they are concealed the offsets make an unsightly appearance, and it is frequently very inconvenient to put them in on account of the arrangement of the building.

. 33 . 34

In one large 16-story building with which the author is acquainted, a loop, as indicated in Figure 34, was made with each riser and sealed in the seventh floor; but he would not recommend this arrangement, inasmuch as leaks are most apt to occur at the points marked C when the expansion and contraction works on the threads of the joint. Besides this, the framing of the building and extra construction details in the floor necessary to conceal these offsets are difficult and expensive. The expansion of such risers is frequently taken care of by means of expansion joints, a diagram of which is shown in Figure 35. The author has used these joints to a large extent, and although in some localities there is a prejudice against them, he thinks this rather unwarranted. By proper arrangement the expansion risers in any building not over 12 or 14 stories high can be taken care of with one set of expansion joints. In a 14-story building heated on the overhead system the author installed an expansion joint in each riser above the radiator connection at the seventh floor. The risers were anchored rigidly to the beams of the fifth and twelfth floors so that expansion was in both directions from these points. This gave about ¾ inch expansion downward at the first and eighth floors and about ¾ inch upward at the seventh and fourteenth. Radiator connections on the eighth floor were long enough to admit of