Colonel Barriffe provides this* to illustrate the way all members of a unit should be arrayed in preparation for battle.  Not only are pikemen and musketeers represented here but so are others: captain or commander, lieutenant, drummers, sergeants and ensign (flag bearer for those new to this). Note and remember the positions of each kind in relation to the others. The commander and ensign are at the front to lead, to orient and to inspire the soldiers (plus the commander has to see what to do next).  Sergeants are at each corner to coordinate and to be sure all soldiers within shouting distance obey the commander's orders.  Drummers are at the front and rearmost ranks, here between the musketeers and the pike.  Drummers, with their drumbeats, repeat and emphasize the commands.  At the rear is the lieutenant, placed there primarily to keep him protected so that he would be available to step forward to take command should the commander fall.  The lieutenant can also provide guidance from his position and be sure no soldier shirks his duty. A lexicon of symbols used in the above diagram: C - captain or commander D - drummer E - ensign L - lieutenant M - musketeer P - pikeman S - sergeant Sergeant Subtlelus says: The new soldier in his first battle will quickly come to understand that the ensign and drummers are not mere ornaments for the unit.  With the copious smoke produced by musket and cannon, and their din, plus the shouts and cries across the battlefield, the ensign and drummers provide sometimes the only communication that can reach a soldier.     *Chapt. 7, Military Discipline...