\begin{table}%t1
\caption{Comparison between our dynamical masses
and spectroscopic masses from Kudritzki et~al. (\cite{KUP06}). Observed
mass-loss rates from the same paper are also listed and compared to
values from the model tracks of Bl\"ocker (\cite{B95}). He~2-108 is classified 
as {\it wels}, the other three are non-emission-line stars.}\label{sp_mass} 
%\centering
\small
\begin{tabular}{lllllll}
\hline
\hline
 Object & \multicolumn{2}{c}{$M$~[$M_\odot$]} & 
  \multicolumn{2}{c}{$T_{\rm eff}$~[$10^3$~K]} &  
  \multicolumn{2}{c}{$\log \dot M $~[$M_\odot$~yr$^{-1}$]} \\
        & dyn.  & spec.  & dyn. & spec. & spec. &evol. tracks\\
\hline
\object{Tc~1}     & 0.59 & 0.81 & 32 & 34 & $-7.46$ & $-7.91$ \\
\object{He~2-108} & 0.57 & 0.63 & 32 & 34 & $-6.85$ & $-8.16$ \\
\object{IC~418}   & 0.61 & 0.92 & 37 & 36 & $-7.43$ & $-7.82$ \\
\object{NGC~3242} & 0.61 & 0.63 & 79 & 75 & $-8.08$ & $-7.86$ \\
\hline
\end{tabular}
\end{table}