devised were small piers built of a framework of wood supported either by empty petrol tins or by bundles of cork slabs: piers which were so devised that they could be used either as rafts to carry a single man across the Canal or as supports for foot-bridges for taking a continuous stream of men in single file. In addition collapsible boats had been provided, together with mud-mats and scaling-ladders for negotiating stretches of mud and the steep brick walls of the Canal banks. Finally, some genius hit on the novel idea of making use of life-belts on a considerable scale. The latter idea in particular promised considerable prospects of success; the authorities at Boulogne were telegraphed for the life-belts from some of the leave-boats, and over 3,000 were collected and were sent up and issued to the storming troops.
On the 27th September arrangements were made for a dress rehearsal to take place, and men loaded with full kit as for a storming party were detailed to test each type of means for crossing the Canal. The first attempt was made near Bihecourt, but enemy shelling of batteries in the vicinity was so persistent and interfered so much with the preparations for the trial that it was postponed by order of General Campbell until the next day. On the 28th, therefore, the party proceeded to the moat at Brie Château on the Somme, where the practice was carried out in front of the Divisional Commander in the pouring rain, but with good results. It was discovered by actual experience that the collapsible boats, which required four men apiece to carry them, could be opened and launched in twenty seconds, while men, weighted with their storming kit but supported with life-belts fixed high up on their bodies, were able to swim across a stretch of deep water, forty yards in breadth, and could not drown. Similar experiments were made with a man who
