Complex sentence: The term "Ammunition boots" comes from the boots'unusual source; they were procured by the Master Gunner and the Munitions Board at Woolwich (the Regiment of Artillery's headquarters) rather than Horse Guards (the headquarters of the British Army).
Split into simpler sentences: The term "Ammunition boots" comes from the boots'unusual source. They were procured by the Master Gunner and the Munitions Board at Woolwich (the Regiment of Artillery's headquarters) rather than Horse Guards (the headquarters of the British Army).