Open Order - in the Files
Open Order in the files is the preferred spacing for the march. With sufficient distance between one soldier and the next in front, there is room for the butt end of a shouldered pike to be near the ground and not trip the person in front. For musketeers, the muzzle of a shouldered gun is not inches from the face of the following soldier. All can view more ground immediately ahead of each step than with Order, which is a consideration on rough ground.
There are three ways to determine distancing in files for Open Order. For all methods, the result should be slightly less than two meters or approximately six feet between soldiers.
Note: the only difference between these commands and the ones for Order is the addition of one word in each: "Open." All soldiers should listen closely to their superiors in order to catch this little addition.
(Remember, a file is 90 degrees to a rank and each file member is in a different rank.)