Winston Churchill: The World Crisis:
Sir Douglas also describes his own preparations, which were thorough and straightforward:
Vast stocks of ammunition and stores of all kinds had to be accumulated beforehand within a convenient distance of our front. To deal with these many miles of new railways— both standard and narrow gauge— and trench tramways were laid. All available roads were improved, many others were made, and long causeways were built over marshy valleys…. Scores of miles of deep communication trenches had to be dug, as well as trenches for telephone wires, assembly and assault trenches, and numerous gun-emplacements and observation posts.
Thus there was no chance of surprise. Nothing could be introduced to obscure the plain trial of strength between the armies, or diminish the opportunities for valour on the part of the assaulting troops. For months the Germans had observed the vast uncamouflaged preparations proceeding opposite the sector of attack. For a week a preliminary bombardment of varying but unexampled intensity had lashed their trenches with its scourge of steel and fire. Crouched in their deep chalk caves the stubborn German infantry, short often through the cannonade of food and water, awaited the signal to man their broken parapets.
The lanes which the British shrapnel had laboriously cut through their barbed-wire entanglements were all carefully studied, and machine guns were accurately sited to sweep them or traverse the approaches with flanking fire. Even one machine gun in skilled resolute hands might lay five hundred men dead and dying on the ground; and along the assaulted front certainly a thousand such weapons scientifically related in several lines of defence awaited their prey. Afar the German gunners, unmolested by counter-battery, stood ready to release their defending barrages on the British front lines, on their communication trenches and places of assembly...