William Duane, A military dictionary
“ Whenever the battalion wheels into open column, in order to prolong the line on which it was formed, and that no distant point in that prolongation is previously given, the serjeant guide of the leading company will advance 15 or 20 paces, and place himself in the line of the pivot flanks, and the leading officer will thereby (taking a line over his head) be enabled to ascertain the direction in which he is to move. ”
