Solid state NMR, MRI and Sir Peter Mansfield: (1) from broad lines to narrow and back again; and (2) a highly tenuous link to landmine detection

The contributions of Sir Peter Mansfield to MRI are rooted in solid state NMR. I summarize some of the important contributions of Sir Peter to that field, provide a glimpse of the state of the art in multiple-pulse line-narrowing in the early 1970s, and indicate how the earliest MRI efforts at Nottingham flowed from solid state NMR. These line-narrowing methods, providing control over the Hamiltonian governing the dynamics of nuclear spins, continue to evolve and to find new uses. I indicate how some methods and ideas from solid state NMR of the 1970s are at present applied to the detection of explosives in landmines by nuclear quadrupole resonance (NQR).