History of the Peloponnesian War

After this followed the battle. The Argives and their confederates marched to the charge with great violence and fury. But the Lacedaemonians slowly and with many flutes, according to their military discipline, not as a point of religion, but that, marching evenly and by measure, their ranks might not be distracted, as the greatest armies, when they march in the face of the enemy, use to be.

Whilst they were yet marching up, Agis, the king thought of this course. All armies do thus. In the conflict they extend their right wing so as it cometh in upon the flank of the left wing of the enemy: and this happeneth for that every one, through fear, seeketh all he can to cover his unarmed side with the shield of him that standeth next to him on his right hand, conceiving that to be so locked together is their best defence. The beginning hereof is in the leader of the first file on the right hand, who ever striving to shift his unarmed side from the enemy, the rest upon like fear follow after. And at this time, the Mantineans in the right wing had far encompassed the Sciritae;