Possible Clues:

• Not the sole thing you 31 across with
• How the little dears get back to the North if it's just over one foot
• You must keep it during March
• One part of Oxford just like all the others?
• The Foot must keep it and have it on foot
• It's over one foot to get the little dears back to Ulster
• Part of foot between toes and ankle
• Keeping pace, though on foot
• Part of foot (how to march!)
• Marching like this over one foot