Engineering Wonders of the World
Volume I

436 ENGINEERING WONDERS OF THE WORLD. Floating the first Span. pontoons were then brought into position under the gir- ders just be- fore the tide was expected an hour after girders were to rise. Half the ebb the afloat, and shortly afterwards were moved out from the jetties, as shown in Fig. 2. Groups of anchors had been Fig. 5.—PONTOON REMOVED FROM BELOW SPAN. Fig. 4.-THE SPAN IN POSITION OVER PIERS READY FOK LOWERING. difficulty was got over, how- ever, by jacking up the gir- ders on sleeper stacks on the shore staging, and by lower- ing them on other eight-foot stacks on top of the bridge piers. Th© girders, after being safely placed, were lowered down to their proper level with jacks. The last span was launched on June 30, 1907. The sec- ond floating was more diffi- cult than the first, because placed in the river at suitable places, and men on the pontoons hauled on these until the float- ing girders were brought into mid-river (Fig. 3), and then hauled on other anchors placed in the river above the bridge. In about four hours from starting the girders were brought into position as in Fig. 4, the pontoons being still in position under the span. The pon- toons were removed partly by the falling tide, and partly by letting water into them through cocks specially provided. The last span was ready for floating by the end of June. The river had by this time risen eight feet, and was too high to be affected by the tide. The pontoon staging was therefore eight feet too high. This The final Span—a Difficulty. the men had to haul up against a strong current. But the Bombay Khallassies. directed by the engineer, worked well, and proved stronger than the current. It took some time to remove the pontoons, as in this case the river tended to rise rather than sink. It was dark when the “ Dread- nought ” was finally started on her return journey. She had no sooner left the bridge than a terrific squall burst upon her. For- tunately, though the wind was in the wrong direction, the direction of the current was in her favour, and so the strange craft was re- turned safely to her anchorage. Much work remained to be done to com- plete the bridge. On August 4, 1907, however, the first engine passed over it with three