In his day job as a chemistry professor at the University of Florida his students called him the Colonel. At night, he becomes a singer/songwriter and musician. Chuck Martin is the band leader, lead vocalist and lead guitar player of The Righteous Kind. The Righteous Kind celebrates its four-year anniversary tonight playing at this week’s Free Friday’s concert at the Bo Diddley Plaza in downtown Gainesville. Florida’s 89.1, WUFT-FM’s Paula Cunniffe reports.