  We review the theory of JNR, mass 1/2 hyperbolic monopoles in particular
their spectral curves and rational maps. These are used to establish conditions
for a spectral curve to be the spectral curve of a JNR monopole and to show
that that rational map of a JNR monopole monopole arises by scattering using
results of Atiyah. We show that for JNR monopoles the holomorphic sphere has a
remarkably simple form and show that this can be used to give a formula for the
energy density at infinity. In conclusion we illustrate some examples of the
energy-density at infinity of JNR monopoles.
