  We show that the laws of electromagnetism in $(D+1)$-dimensional Minkowski
space-time $\mathcal{M}$, explicitly for $D=1$, $2$ and $3$, can be obtained
from an integral representation of the zero-curvature equation in the
corresponding loop space $\mathcal{L}^{(D-1)}(\mathcal{M})$. The conservation
of the electric charge can be seen as the result of a hidden symmetry in this
representation of the dynamical equations.
