  Properties of Riesz capacity are developed with respect to the kernel
exponent $p \in (-\infty,n)$, namely that capacity is monotonic as a function
of $p$, that its endpoint limits recover the diameter and volume of the set,
and that capacity is left-continuous with respect to $p$ and is
right-continuous provided (when $p \geq 0$) that an additional hypothesis
holds. Left and right continuity properties of the equilibrium measure are
obtained too.
