=361.= At the preliminary instruction (conducted without formal command) the instructor has two troopers on the right of the rank move forward a convenient distance and halt. He then aligns these two troopers carefully, with the proper interval as =in line= (par. 368-_a_), and causes the other troopers to note the details of the alignment. The other troopers are then required to move up one at a time and align themselves, with the correct interval, on the line thus established. The troopers move forward, in order from right to left, at successive repetitions by the instructor of the caution =NEXT=. Each trooper, when on or near the line, executes =eyes right= (par. 64), aligns himself accurately on the line established by the trooper or troopers on his right, and looks to the front as soon as he thinks himself correctly aligned. The instructor explains and corrects any errors. Similar instruction is given the troopers in aligning themselves to the left. As soon as reasonable proficiency is attained but a single trooper is moved forward, and the alignment is made in the same manner upon the single trooper established as the base. The instruction is similarly given with the center trooper moved to the front as a base. Two troopers, one on the right, the other on the left of the base, then move forward at each repetition of the caution =NEXT=. The instructor observes in the mounted instruction: That each trooper moves his horse promptly and halts with his horse correctly disposed; that he sits squarely on his horse without advancing either shoulder or leaning his body to the front or rear; that he dresses promptly as he arrives on the line; and that he makes proper use of the aids (pars. 200 to 208). In the first drills the basis of the alignment is established parallel to the front of the section; afterwards in oblique directions. =362.= When the troopers have acquired reasonable proficiency in aligning themselves, as above, the alignment is executed at the command =DRESS=, given by the instructor from his position as leader. The trooper designated as the guide (par. 371) is always the base trooper of the alignment and places himself accurately 3 yards in rear of the leader. All the other troopers align themselves promptly on the base trooper, continuing to look toward him until the command, =FRONT=. At this last command, given when the alignment is completed, all turn the head and eyes quickly to the front and take the position of =attention= (pars. 59, 198). Movements in the rank then cease. The instructor then habitually faces the squad or goes to either flank to verify the accuracy of the dressing, first cautioning the guide to remain in place.