The Bayonet Drill

For when the enemy charge did arrive, Bayonet drill in the British Army also encouraged its soldiers to fight as units and not as individuals. The bayonet drill was introduced for the Battle of Culloden, in order to defeat the much vaunted Highland charge; it was not for a soldier to protect himself or to attack the enemy in front, but to stab into the unprotected side of the man attacking his neighbour, each man in the battle line relying on his comrades to defend him.

http://en.wikipedia.org/wiki/Human_wave_attack

Thanks to Toutie for the tip.