The Agricultural Revolution, the fifth step in the Mechanical <l:6,66>Advances<e>, marks the impact of higher learning on agriculture and trade. These advantages are embodied in the <l:2,18>Mill<e>, which increases <l:6,93>production<e>, the <l:8,1>advanced farm<e>, which increases <l:6,90>food<e>, and the <l:1,17>Pikemen<e>, who provide cheap defensive protection. The proper tools and accumulated knowledge also allow for <l:6,35>terraforming<e> <l:5,6>Swamps<e>.