FORT HUACHUCA — At exactly 2:20 p.m. on Friday, five soldiers took a knee and placed shiny spurs on their boots. “Ladies and gentlemen, I introduce you to the newest members of the B Troop, 4th Cavalry Division,” said Garrison Commander Col. Whit Wright to the crowd. A wave of cheers followed. For close to 16 weeks, the group — four men and one woman — learned all things 1880s as they now represent the Fort’s historic horseback soldier. Sgt. Kascia Vigil, the class’s only female student, joined the troop as it “was something prideful about them.” “This training was...