  We report on the first measurement of Mutual Coulomb Dissociation in heavy
ion collisions. We employ forward calorimeters to measure neutron multiplicity
at beam rapidity in peripheral collisions. The cross-section for simultaneous
electromagnetic breakup of Au nuclei at $\sqrt{s_{NN}}=130$ GeV is
$\sigma_{MCD}=3.67\pm 0.25$ barns in good agreement with calculations.
