\begin{table}%t1
%\centering
\par
      \caption{ A part of our measurements. It shows angular separations, 
                  positions angles, as well as instrumental $V$
                  magnitude differences of visual double stars.}
         \label{t2}
\begin{tabular}{rrl rrl c rr rr rr r r } \hline\hline
\multicolumn{3}{c}{$\alpha_{2000}$} &
\multicolumn{3}{c}{$\delta_{2000}$} &
\multicolumn{1}{c}{WDS} &
\multicolumn{1}{c}{$\rho$} &
\multicolumn{1}{c}{$\sigma_{\rho}$} &
\multicolumn{1}{c}{$\theta$} &
\multicolumn{1}{c}{$\sigma_{\theta}$} &
\multicolumn{1}{c}{$\Delta V$} &
\multicolumn{1}{c}{$\sigma_{\Delta V}$} &
\multicolumn{1}{c}{Epoch} &
\multicolumn{1}{c}{No.} 
\\ \hline
\multicolumn{1}{c}{h} &
\multicolumn{1}{c}{m} &
\multicolumn{1}{c}{s} &
\multicolumn{1}{c}{\degr} &
\multicolumn{1}{c}{\arcmin} &
\multicolumn{1}{c}{\arcsec} &
\multicolumn{1}{c}{} &
\multicolumn{2}{c}{\arcsec} &
\multicolumn{2}{c}{\degr} &
\multicolumn{2}{c}{magnitudes} &
\multicolumn{1}{c}{year} &
\multicolumn{1}{c}{ } \\ \hline
% &    &       &     &    &    &            & . . .  &       &        &      &       &       &         &    \\
1 & 52 & 10.1  & +66 & 26 & 56 & 01522+6627 & 29.515 & 0.016 & 315.83 & 0.03 & 2.695 & 0.003 & 2003.60 & 15 \\
2 & 42 & 21.3  & +38 & 37 & 07 & 02424+3837 & 14.562 & 0.008 & 343.41 & 0.05 & 1.521 & 0.002 & 2004.91 & 16 \\
2 & 55 & 47.1  & +34 & 28 & 40 & 02558+3429 & 21.519 & 0.012 & 148.78 & 0.02 & 1.421 & 0.001 & 2004.91 & 16 \\
3 & 02 & 16.8  & +41 & 23 & 46 & 03023+4124 & 17.602 & 0.010 & 162.88 & 0.05 & 1.822 & 0.002 & 2004.91 & 16 \\
3 & 22 & 51.8  & +29 & 49 & 06 & 03229+2949 & 10.438 & 0.006 & 101.38 & 0.02 & 0.176 & 0.001 & 2004.91 & 16 \\ 
\hline
\end{tabular} 
\end{table}