Each platoon leader puts into execution the commands or directions of the captain, having first taken such precautions to insure correct sight setting and clear description of the target or aiming point as the situation permits or requires (par. 141); thereafter he gives such additional commands or directions as are necessary to exact compliance with the captain's will. He corrects the sight setting when necessary. When the target can not be seen with the naked eye, he designates an aiming point (by one of the methods described in par. 141 if necessary) and orders fire upon it, first announcing the proper sight setting to correct the error of aim. In general, =platoon leaders= observe the target and the effect of the fire and are on the alert for the captain's commands; they observe and regulate the rate of fire. The =file closers= watch the firing line and check every breach of fire discipline. =Chiefs of section= transmit commands when necessary, observe the conduct of their sections and abate excitement, assist in enforcing fire discipline, and participate in the firing unless otherwise directed by the =platoon commanders=. The best troops are those that submit longest to fire control. To avoid or delay such loss of control should be the constant aim of all. Fire control implies the ability of the commander to stop the firing, change the sight setting and target, and resume a well-directed fire. FIRE DISCIPLINE. =664.= Fire discipline implies, besides an unquestioning habit of obedience to commands, a control of the rifle by the soldier (the result of training), which will enable him in action to make hits instead of misses. It embraces taking advantage of the ground; proper understanding of orders as to target designation; care in setting the sight and delivery of fire; constant attention to the orders of the leaders, and careful observation of the enemy; an increase of fire when the target is favorable, and a cessation of fire when the enemy disappears; economy of ammunition. Orderly and regular methods on the part of leaders aid fire discipline. Self possession and a confident tone in giving commands and instructions are indispensable. In combat, shots which graze the enemy's trench or position, and thus reduce the effectiveness of his fire, have the approximate value of hits; such shots only, or actual hits, contribute toward fire superiority. Fire discipline implies that, in a firing line without leaders, each man retains his presence of mind and directs effective fire upon the proper target.