463. The line of battle may be marked or determined in three different manners: 1st, by placing two markers eighty or a hundred paces apart, on the direction it is wished to give to the line; 2nd, by placing a marker at the point at which it may be intended to rest a flank, and then choosing a second point toward the opposite flank, and there posting a second marker distant from the first a little less than the front of the subdivision; 3rd, by choosing at first the points of direction for the flanks, and then determining, by intermediate point, the straight line between those selected points, both of which may sometimes be beyond reach.