\begin{table}%t1
\caption{Proper motions of thin filaments.\label{tab1}} 
\small 
%\centerline
 {\begin{tabular}{lccccccc}
\hline\hline
\noalign{\smallskip}
Feature & $\Delta\alpha$$^a$ & $\Delta\delta$$^a$ &
${\rm Size}~ (\Delta x \times \Delta y)$& $v$$^b$  & $\Delta v$ & $\phi$$^c$ &$v_{\rm esc}$\\
 & (arcsec) &(arcsec) &(arcsec~$\times$~arcsec) &(km$~$s$^{-1}$)&(km$~$s$^{-1}$)& ($^{\circ}$) & (km$~$s$^{-1}$)\\
\hline
NE1        &   4.76 &  3.42 & $0.32\times0.46$ &  --29 & 16 &  90 & 368\\
NE3        &   2.62 & --0.09 & $0.38\times0.41$ &  167 & 25 & 140 & 550\\
%NE4       &   0.32 & -1.95 & 0.43$\times$0.43 &  130 & 18 & 155\\
SW3       &  --6.08 & --0.77  & $0.35\times0.35$ & --229 & 19 & 270 & 360 \\
SW4       &  --5.07 &  1.76  & $0.43\times0.38$ &  --92 & 16 & 305 & 404\\
SW5a      &  --4.20 & --2.31  & $0.35\times0.11$ & --165 & 15 & 270 & 407\\ 
SW5b      &  --4.13 & --2.75  & $0.16\times0.24$ & --123 & 22 & 240 & 400\\ \hline 
NE4 (RA) &   0.50 & --1.63 & $2.51\times1.97$ & --386 & 76 &  & 682\\
NE4 (Dec) &        &       &                  & --280 & 55 &  &\\ 
NE4 (along) &       &       &                  & --436 & 103 & 240 & \\
NE4 (perp.) &       &       &                  &  194 & 11 & 150 &\\ \hline
SW7 (RA) &  --3.07 & --5.10 & $0.73\times1.22$ & --186 & 17 &   &  365\\
SW7 (Dec) &        &       &                  &  --80 & 21 &   & \\ \hline
X1  (RA) &   3.22 &  3.40 & $0.30\times0.38$ &  113 & 16 &   & 412\\
X1  (Dec) &        &       &                  &  --78 & 21 &   & \\ \hline
X7  (RA) &  --0.56 & --0.55 & $0.54\times0.41$ &  --71 & 17 &   & 1006\\
X7  (Dec) &        &       &                  &  458 & 21 &   & \\ \hline
X3  (RA) &  --2.45 & --2.37 & $0.46\times0.43$ &  --78 & 18 &   & 483\\ 
X3  (Dec) &        &       &                  &  135 & 20 &   & \\
\hline
\end{tabular}}
\par
\smallskip
$^a$ {Relative to SgrA*; position of the center of the box;}
$^b$ {velocities of all NE and SW features, except that of SW7 and NE4, are in a direction approximately perpendicular to the feature. Other proper motions are given both in RA and Dec  direction. In case of NE4 we additionally give the velocity along the feature and perpendicular to it. The positive sign in the velocity refers to the eastward motion in RA and northward in Dec. For the perpendicular component the positive sign marks the predominant eastward motion. The negative sign for the motion of the NE4 along the filament marks the predominant southward component;}
$^c$ {the position angle of the velocity vector for the features with a proper motion measured in the direction perpendicular to the feature. The angle is measured east of north.}
\end{table}