  We contend that Microwave Spin Pumping was first predicted and observed -
albeit using a different and more sensitive detection mechanism than Inverse
Spin Hall Effect - in the 1950's. This discovery was the founding step in the
widely used analytical tool that is now known as Dynamic Nuclear Polarisation.
Recognising this hitherto unsung connection between 20th Century Magnetic
Resonance and 21st Century Spintronics not only helps to explain and unify
contemporary metallic spin pumping observations: it is also the key to
unlocking the immense and very sophisticated toolbox of Magnetic Resonance and
placing it at the disposal of the future of Spintronics.
