  We show that recent experiment data for the ratios $E_{1^+}/M_{1^+}$ and
$S_{1^+}/M_{1^+}$ can be explained in a dynamical model for electromagnetic
production of pions, together with a simple scaling assumption for the bare
$\gamma^* N \Delta$ form factors. Within our model we find that the bare
$\Delta$ is almost spherical and the electric E2 and Coulomb C2 quadrupole
excitations of the physical $\Delta$ are nearly saturated by pion cloud
contribution in $Q^2 \le 4.0 GeV^2$.
