shells and bullets in their final stage of development in World War I are: They used the property of carrying power, whereby if two projectiles are fired with the same velocity, then the heavier one goes farther. Bullets packed into a heavier carrier shell went farther than they would individually. The shell body itself was not designed to be lethal: its sole function was to transport the bullets close to the target, and it fell to the ground intact after the bullets were released. A battlefield where a shrapnel barrage had been fired was afterwards typically littered with intact empty shell bodies, fuzes and central tubes. Troops under a shrapnel barrage would attempt to convey any of these intact fuzes they found to their own artillery units, as the time setting on the fuze could be used to calculate the shell's range and hence identify the firing gun's position, allowing it to be targeted in a counter-barrage. They depended almost entirely on the shell's velocity for their lethality: there was no lateral explosive effect. A firsthand description of successful British deployment of shrapnel in a defensive barrage during the Third Battle of Ypres, 1917: ... the air is full of yellow spurts of smoke that burst about 30 feet up and shoot towards the earth - just ahead of each of these yellow puffs the earth rises in a lashed-up cloud - shrapnel - and how beautifully placed - long sweeps of it fly along that slope lashing up a good 200 yards of earth at each burst. Tactical use During the initial stages of World War I, shrapnel was widely used by all sides as an anti-personnel weapon. It was the only type of shell available for British field guns (13-pounder, 15 pounder and 18-pounder) until October 1914. Shrapnel was effective against troops in the open, particularly massed infantry (advancing or withdrawing). However, the onset of trench warfare from late 1914 led to most armies decreasing their use of shrapnel in favour of high-explosive. Britain continued to use a high percentage of shrapnel shells. New tactical roles included cutting barbed wire and providing "creeping barrages" to both screen its own attacking troops and suppressing the enemy defenders to prevent them from shooting at their attackers. In a creeping barrage fire was 'lifted' from one 'line' to the next as the attackers advanced. These lines were typically apart and the