The central element of the seal and emblem, the Roman cuirass, is a symbol of strength and defense. The sword, esponton (a type of half-pike formerly used by subordinate officers), musket, bayonet, cannon, cannonballs, mortar, and mortar bombs are representative of Army implements. The drum and drumsticks are symbols of public notification of the Army's purpose and intent to serve the Nation and its people. The Phrygian cap (often called the Cap of Liberty) supported on the point of an unsheathed sword and the motto This We'll Defend on a scroll held by the rattlesnake is a symbol depicted on some American colonial flags and signifies the Army's constant readiness to defend and preserve the United States.