 The silver eagle was selected based on the fact that there were more colonels with the silver eagle that those with gold, primarily in the cavalry and artillery, hence it was cheaper to replace the numerically fewer gold ones in the infantry.At that time on the shoulder straps, lieutenant colonels wore an embroidered silver leaf; majors wore a gold embroidered leaf; and captains and first lieutenants wore gold bars.The second lieutenant had no grade insignia, but the presence of an epaulette or shoulder strap identified him as a commissioned officer.