Victorian illustration to download showing a picture of soldiers constructing a temporary bridge. A large crowd of spectators watch from a bridge, from the shore and from small boats. This event took place in 1867, when the Ist Middlesex Engineers demonstrated the throwing of a barrel-pier bridge across the Serpentine. It was 310ft long, and capable of bearing cavalry. Sections of the bridge, constructed from barrels and planks, were made on land. These were then floated into position and lashed together. The whole exercise took only two hours. ‘When the bridge was completed’, reported the Illustrated London News, ‘the men marched over their structure, headed by their band. This was done amid the loud cheers of all who witnessed the performance.’