Moltke the Elder, Chief of the General Staff from 1857–88, modernized the Prussian Army during his tenure. He expanded the General Staff, creating peacetime subdivisions such as the Mobilization, Geographical-Statistical and Military History Sections. In 1869, he issued a handbook for warfare on the operational level, "Instructions for Large Unit Commanders", writing, "The modern conduct of war is marked by the striving for a great and rapid decision". Moltke was a strong proponent of war game training for officers and introduced the breech-loading needle gun to troops, which allowed them to fire significantly faster than their adversaries. Moltke took advantage of the railroad, guiding the construction of rail lines within Prussia to likely places of deployment. Because modern armies had become too large and unwieldy for a single commander to control, Moltke supported multiple and independent smaller armies in concentric operations. Once one army encountered the enemy and pinned it down, a second army would arrive and attack the enemy's flank or rear. He advocated a "Kesselschlacht", or battle of encirclement.