10750 - 399 L r in which L = length of column in feet r = least radius of gyration. For example, suppose we wish to select a size of pipe suitable for supporting a load of 25,000 pounds, and having a length (or height) of fifteen feet. Along the left hand side of the diagram, under "thousands of pounds" find 25 (i.e. 25 thousands), and then find the length ( = 15 feet) along bottom line of the diagram. Follow the vertical line at 15 feet until it intersects the horizontal line through 25 thousands, and the nearest inclined line above that point will give the diameter of the pipe to be used. In this case a 5-in. diameter will be required.

Fig. 234.

Fig. 235.

Fig. 236.

Fig. 237,

Fig. 238.

Fig. 239.

## Problems

1. Fig. 226 shows a framing plan on which is all the information necessary to detail the different members. Make a detail of column No. 4, assuming that the bottom of the column rests on a cast iron web base 12 ft. below the top of the 15-in. beam No. 9, and that the column is arranged to receive another column of the same size, the joint being 1 ft. 6 in. above the top of the 15-in. beam.

2. Make details covering the 10 to 13-inch beams in Fig. 208.

3. Make a schedule of tie rods and of field bolts required for all framing shown in Fig. 20S.

4. Suppose that in Fig. 199 the cast iron columns had a 12-in., 31 1/2-lb. beam instead of the 15-in. beam, a 7-in. instead of the 10-in. beam, and a 9-in. instead of the 12-in. beam, and that all beams were flush on top and the other features the same as shown in Fig. 210. Make a detail of such a column.

5. Make a bill of material for the column shown in Fig. 224.

6. Given a portion of a framing plan as shown in Fig. 226. Make shop details of (a) beam No. 1 resting on the column, (b) beam No. 2, and (c) channels No. 3 and 4.

7. Given a beam box girder framed between two columns as shown in Fig. 227. Make a shop detail of this girder using a uniform pitch of rivets of 3 in. in the plates.

8. Given a lintel composed of two 10-in., 15-lb. channels framed between two columns, the channels being placed with the flanges turned in, 10 in. back to back, and 14 ft. 8 in. between the faces of columns. Make a complete shop detail and order for all parts.

9. Given a pit under an elevator to be framed with 3 X 3-in., 6.6-lb. Ts, 17-in. on centers, to receive terra cotta tile. These Ts frame between the webs of 15-in., 42-lb. I-beams at each end, which are 7 ft. 3 in. center to center. The distance from the top of the beams to the bottom of the flange of the Ts is 6 in. Make a shop detail of the Ts.

10. Given a portion of a framing plan as shown in Fig. 228. Make a shop detail of beams No, 1 and 2 which are framed between columns.

11. In the above plan make detail covering beams, No. 4 and 5.

12. Given a 15-in., 42-lb. beam framed between the webs of two columns, 20 ft. 8 in. center to center on a line perpendicular to the axis of the webs, and the center of one column is 1 ft. 9 in. off from the other in the direction of the webs. The webs of the columns are 1/2 in. thick. The beam has a 12-ft., 31 1/2-lb. beam framed to it, 2 ft. 1 in. from the center of one column, the tops being flush. There are also holes for two lines of 3/4-in. tie rods. Make shop detail.

OFFICE BUILDING FOR CHICAGO & NORTHWESTERN RAILWAY COMPANY, CHICAGO.

The 52,500-lb. girder for foundations being put in place, showing method of setting heavy girders on solid earth. The girder is lowered near to its proper location; then, with the aid of rollers and stone jacks, it is worked into place gradually. It is secured by hold-fast lines to keep it under control of the workmen.