\begin{table}%t1
\caption{Observed extreme abundances in NGC~6752.}
\label{tabl1}
\begin{tabular}{rccccrr}
\hline
\hline
 & $A_{\rm O}$ & $X_{\rm O}$  & $A_{\rm E}$ & $X_{\rm E}$ & $\Delta A$ & $X_{\rm E}/X_{\rm O}$\\ 
\hline\noalign{\smallskip}
O    &  7.65 & $5.4\times 10^{-4}$   & 7.05  & $1.3\times 10^{-4}$  & $-0.60$   &  0.25 \\
Na   &  4.60 & $6.9\times 10^{-7}$   & 5.35  & $3.9\times 10^{-6}$  &  0.75   &  5.6 \\
Al   &  5.00 & $2.0\times 10^{-6}$   & 6.00  & $2.0\times 10^{-5}$  &  1.00   &  10. \\
Mg   &  6.50 & $5.4\times 10^{-5}$   & 6.38  & $4.7\times 10^{-5}$  & $-0.12$   &  0.87 \\
\mga &  6.42 & $4.7\times 10^{-5}$   & 6.20  & $2.8\times 10^{-5}$  & $-0.22$   &  0.60 \\
\mgb &  5.25 & $3.4\times 10^{-6}$   & 5.40  & $5.3\times 10^{-6}$  & +0.15   &  1.5  \\
\mgc &  5.25 & $3.4\times 10^{-6}$   & 5.85  & $1.4\times 10^{-5}$  & +0.60   &  4.10 \\
\hline
\end{tabular}
\begin{tabular}{l}
Mg24:25:26 \ \ = \ \ 87:6.5:6.5 (O)   and 60:11:29 (E) \\
\hline
\end{tabular}
{\rm A}~=~log(N/H)+12; O: Original; E: Extreme.
\end{table}