=349.= The troopers must be accustomed to conforming, _without the assistance of any command or signal given to the squad as a whole_, to simple movements (e.g., movements =front into line=) initiated at the head of a column formation by a command so given as to be heard by only the leading troopers. With reasonable practice the more essential changes of formation that are executed toward the direction of march can readily be taken by the squad by conforming, without other indication, to the movements of the troopers nearest the leader. As many movements in service must be executed under conditions of noise, dust, etc., that will render it difficult for the commands or signals of the leader to be understood except by those near him, _practice, in conforming promptly and intelligently to the movements of the elements nearest the leader is important and must be given careful attention_. The object ultimately to be sought in the instruction is the quiet, rapid, and effective handling of the squad with a _minimum of either oral commands or signals_. The squad is required to pass rapidly from one formation to another, a new movement being occasionally initiated before the execution of the one preceding it has been completed. TO FORM THE SQUAD, MOUNTED. =350.= To form the squad =in line= (par. 368-_a_), the leader (instructor) designates a trooper to act as the base of the formation, indicates to such trooper the point where the right of the squad is to rest and the direction in which the line is to face, takes position at a convenient distance in front of and facing the point where the center of the squad is to rest, and commands: =LEAD INTO LINE=. The base trooper =leads out= (par. 188) and takes position as indicated; the other troopers lead out so as to approach the line _successively directly from the rear_ and in single rank form on the line established by the base trooper, in order from right to left. The troopers form at stand to horse (par. 187) with intervals of 18 inches between horses. The line having thus formed, the leader calls the roll and commands, =COUNT FOURS= (par. 84). Where there is an incomplete four the troopers in it are cautioned as to the numbers finally assigned them (par. 368-_b_). When but a single trooper is available for an incomplete four the four is habitually broken up and a trooper is placed as an extra file closer. This rule may, however, be modified in connection with the instruction of recruits. The squad having counted fours, the leader causes the squad to mount (par. 358).