Barrage Planning Diagram. This is a planning tool used in the Second Army during the Passchendaele campaign. This shows a short preliminary barrage that would have been used to inflict some losses on the Germans and test coordination and planning on the British side. Not only is the barrage short, but in order to inflict more casualties on frontline infantry, after it started to creep back into the German rear, it suddenly moved forward again for the final few minutes. By showing all the types of fire at oncetwo bands of 18-pounders, 4.5-inch howitzers, machine-guns (which were not firing in this practice barrage), 6-inch howitzers, 60-pounders, 8-inch and 9.2-inch howitzersit allowed planners to graphically record all fire and see at a glance what was intended.
In the original, colors were used to differentiate the elements of the barrage, but this image has been scanned from a black and white copy.