  We determine the critical couplings for the deconfinement phase transition in
$SU(2)$ gauge theory on $N_\tau \times N_\sigma^3$ lattices with $N_\tau = 8$
and 16 and $N_\sigma$ varying between 16 and 48. A comparison with string
tension data shows scaling of the ratio $T_c / \sqrt{\sigma}$ in the entire
coupling regime $\beta =2.30-2.75$, while the individual quantities still
exhibit large scaling violations. We find $T_c / \sqrt{\sigma}=0.69(2)$. We
also discuss in detail the extrapolation of $T_c / Lambda_{\rm{\bar{M}
\bar{S}}}$ and $\sqrt{\sigma} / Lambda_{\rm{\bar{M}\bar{S}}}$ to the continuum
limit. Our result, which is consistent with the above ratio, is $T_c /
Lambda_{\rm{\bar{M}\bar{S}}} = 1.23(11)$ and $\sqrt{\sigma} /
Lambda_{\rm{\bar{M}\bar{S}}} = 1.79(12)$. We also comment upon corresponding
results for $SU(3)$ gauge theory and four flavour QCD.
