\begin{table}%t7
\caption{\label{t:ColDensMasses}Column densities $N$ and masses $M$ from H$^{13}$CO$^+$ lines.}
%\centering
\small
\begin{tabular}{lr@{}c@{}lr@{}c@{}lcccccc}
\hline\hline\noalign{\smallskip}
Source	& \multicolumn{3}{c}{\makebox[3em][c]{$\Delta v$}} & \multicolumn{3}{c}{$T_{\rm A}^*$} 
        & $N_{J=3}$      & $T_{\rm ex}$ 
        & $N_{\rm tot}$(H$^{13}$CO$^+$)$^{(a)}$ & $N$(H$_2$)$^{(a)}$    & $M$ $^{(b)}$	\\
	& \multicolumn{3}{c}{\km}                       & \multicolumn{3}{c}{K}       
        &  cm$^{-2}$	& K
        &  cm$^{-2}$                          & cm$^{-2}$         & \Msun		\\
\hline\noalign{\smallskip}
SgrB2MC	    & 14.7&$\;\pm\;$&.49&3.61&$\;\pm\;$&.62&\dex{(6.4\pm.1)}{12}& 9.6& \dex{5.6}{14}& \dex{2.8}{23}& ---  \\
G10.62-0.38 & 7.15&     &.08&4.12&     &.41&\dex{(3.6\pm.1)}{12}&10.6& \dex{2.7}{14}& \dex{1.4}{23}& \dex{(4.1\pm2.2)}{2} \\
G28.20-0.04N& 9.35&     &.34&0.52&     &.02&\dex{(5.9\pm.3)}{11}& 3.7& \dex{1.3}{15}& \dex{6.4}{23}& \dex{(1.7\pm0.9)}{3} \\
G31.41+0.31 & 5.93&     &.29&1.16&     &.05&\dex{(8.3\pm.4)}{11}& 4.9& \dex{4.5}{14}& \dex{2.2}{23}& \dex{(6.7\pm3.5)}{2} \\
G32.80+0.19 & 7.48&     &.22&1.26&     &.03&\dex{(1.1\pm.1)}{12}& 5.1& \dex{5.2}{14}& \dex{2.6}{23}& \dex{(2.9\pm1.5)}{3} \\
G33.13-0.09 & 5.16&     &.41&0.34&     &.02&\dex{(2.1\pm.2)}{11}& 3.4& \dex{8.4}{14}& \dex{4.2}{23}& \dex{(1.3\pm0.7)}{3} \\
G34.26+0.15B& 5.40&     &.14&2.65&     &.06&\dex{(1.7\pm.1)}{12}& 7.8& \dex{2.3}{14}& \dex{1.1}{23}& \dex{(1.9\pm1.0)}{2} \\
G35.20-1.74 & 4.20&     &.17&0.81&     &.03&\dex{(4.1\pm.2)}{11}& 4.3& \dex{4.2}{14}& \dex{2.1}{23}& \dex{(2.9\pm1.5)}{2} \\
G43.89-0.78 & 3.52&     &.18&0.61&     &.03&\dex{(2.6\pm.2)}{11}& 3.9& \dex{4.4}{14}& \dex{2.2}{23}& \dex{(2.1\pm1.1)}{3} \\
W51D	    & 7.74&     &.29&1.73&     &.05&\dex{(1.6\pm.1)}{12}& 6.0& \dex{4.2}{14}& \dex{2.1}{23}& \dex{(7.8\pm4.1)}{2} \\
G81.67+0.53 & 6.90&     &.06&2.03&     &.02&\dex{(1.7\pm.1)}{12}& 6.6& \dex{3.4}{14}& \dex{1.7}{23}& \dex{(2.6\pm1.5)}{2} \\  
G81.68+0.54 & 2.12&     &.05&1.98&     &.04&\dex{(5.1\pm.2)}{11}& 6.5& \dex{1.1}{14}& \dex{5.3}{22}& \dex{(2.0\pm1.1)}{1}\\  
G45.07+0.13 & 7.21&     &.28&1.03&     &.03&\dex{(9.0\pm.4)}{11}& 4.7& \dex{6.0}{14}& \dex{3.0}{23}& \dex{(1.0\pm0.5)}{3} \\
\hline					
\end{tabular}
\tablefoot{\tablefoottext{a}{Assuming a 50\% uncertainty in  $N_{\rm tot}$(H$^{13}$CO$^+$) which propagates to~$N$(H$_2$); see text;}
\tablefoottext{b}{assuming the same source sizes as in Table~\ref{t:FlowVel}.}} 
\vspace*{3mm}
\end{table}