  The Stieltjes constants $\gamma_k(a)$ appear as the coefficients in the
regular part of the Laurent expansion of the Hurwitz zeta function $\zeta(s,a)$
about $s=1$. We present the evaluation of $\gamma_1(a)$ and $\gamma_2(a)$ at
rational argument, being of interest to theoretical and computational analytic
number theory and elsewhere. We give multiplication formulas for $\gamma_0(a)$,
$\gamma_1(a)$, and $\gamma_2(a)$, and point out that these formulas are cases
of an addition formula previously presented. We present certain integral
evaluations generalizing Gauss' formula for the digamma function at rational
argument. In addition, we give the asymptotic form of $\gamma_k(a)$ as $a \to
0$ as well as a novel technique for evaluating integrals with integrands with
$\ln(-\ln x)$ and rational factors.
