  Using heavy baryon chiral perturbation theory to one loop, we derive an
analytic and parameter-free expression for the momentum dependence of the
strange magnetic form factor of the nucleon $G_M^{(s)} (Q^2)$ and its
corresponding radius. This should be considered as a lower bound. We also
derive a model-independent relation between the isoscalar magnetic and the
strange magnetic form factors of the nucleon based on chiral symmetry and SU(3)
only. This gives an upper bound on the strange magnetic form factor. We use
these limites to derive bounds on the strange magnetic moment of the proton
from the recent measurement of $G_M^{(s)} (Q^2=0.1 GeV^2)$ by the SAMPLE
collaboration. We stress the relevance of this result for the on-going and
future experimental programs at various electron machines.
