\begin{table}%t2
%\centering
\par
\caption{Dry and wet tropospheric zenith path delays ($\tau_{\rm dtrp}$
  and $\tau_{\rm wtrp}$) at the VLBA stations along with the adopted rms
  errors $\Delta\tau_{\rm dtrp}$ and $\Delta\tau_{\rm wtrp}$ in our {\it Monte
  Carlo} simulations.
\label{delay}}
\begin{tabular}{lcccccccc} \hline\hline
    Stations             &\multicolumn{2}{c}{Dry trop.}&&\multicolumn{5}{c}{Wet trop.}\\
&&&&\multicolumn{2}{c}{Mean}&&\multicolumn{2}{c}{Max}\\
\noalign {\vskip 0.0mm}
\noalign {\vskip 1.0mm}
                         &$\tau_{\rm dtrp}$&$\Delta\tau_{\rm dtrp}$&&$\tau_{\rm wtrp}$&$\Delta\tau_{\rm wtrp}$&&$\tau_{\rm wtrp}$&$\Delta\tau_{\rm wtrp}$\\
                         &     (cm)       &   (cm)    &&    (cm)        &   (cm)    &&   (cm)       &  (cm)  \\\hline
    Brewster             &      225       &    0.5    &&       ~8       &     2.7   &&    13        &  ~4.3  \\
    Fort Davis           &      192       &    0.5    &&       ~8       &     2.7   &&    15        &  ~5.0  \\
    Hancock              &      223       &    0.5    &&       ~9       &     3.0   &&    19        &  ~6.3  \\
    Kit Peak             &      185       &    0.5    &&       ~6       &     2.0   &&    15        &  ~5.0  \\
    Los Alamos           &      185       &    0.5    &&       ~6       &     2.0   &&    13        &  ~4.3  \\
    Mauna Kea            &      149       &    0.5    &&       ~1       &     2.0   &&    ~4        &  ~2.0  \\
    North Liberty        &      225       &    0.5    &&       10       &     3.3   &&    19        &  ~6.3  \\
    Owens Valley         &      199       &    0.5    &&       ~5       &     2.0   &&    20        &  ~6.7  \\
    Pietown              &      176       &    0.5    &&       ~4       &     2.0   &&    12        &  ~4.0  \\ 
    Saint Croix          &      213       &    0.5    &&       22       &     7.3   &&    30        &  10.0  \\ \hline
\end{tabular}
\end{table}