  We present an intersection-theoretical approach to the invariants of plane
curve singularities $\mu$, $\delta$, $r$ related by the Milnor formula
$2\delta=\mu+r-1$. Using Newton transformations we give formulae for $\mu$,
$\delta$, $r$ which imply planar versions of well-known theorems on
nondegenerate singularities.
