"National Roman Legion"

[caiusbeerquitius]

The small relief band on the arch of Orange is really telling here. The motions displayed are impossible in a dense formation. Polybios says that each legionary had 6x6feet space in the front, whereas the phalanx only had 3x3 (ca. 180 by 180 cm and 90 by 90 cm) Vegetius gives 3 feet front and 7 feet depth. looking at the arch of Orange Polybius seems to give the best account. Covered by a large shield with a certain width, a three foot wide "slot" would give a soldier only between 30 and 15 cm space for his arm. I wonder how one would fight with a sword in such a formation - the scenes on the arch of Orange would be impossible, anyway.
See especially here:
www.romanarmy.com/cms/component/option,com_easygallery/act,photos/cid,278/Itemid,135/

The dense formations as seen on Trajans column and the Column of Marcus are 1.st artistic convention (compare to the Parthenon frieze) and 2nd propaganda / monumental art. IMO the dense formations were used, but rather during sieges , for defence, etc.

One might also consider the lack of possibilities for soldiers to show virtus in a too dense formation.