%  Definitions and stuff for chemistry, equilibrium symbols :
%  \eqbm  -- unlabeled equilibrium (longer than harpoons)
%  \eqbmlab~#1_#2 -- long equilibrium sign with forward (#1) and backward (#2)
%                    labels
%  \yields       -- long right arrow
%  \yieldslab~#1 --  ``    ``      ``  with a label above (#1)
%    To typeset chemical equations,
%  type \rm just after the $ or $$.  Also, when using \eq}align or
%  \eq}aligno, type \cr\rm wherever you would normally type \cr.
%  The labels on \eq}bmlab and \yieldslab come out in italic automatically
%  (use \rm to get roman).  Elsewhere, italicize variables like K_W or N_0
%  using \cit.
%
\def\cit{\fam=-1}   \% Chemistry ITalic
\def\longrharpup{\relbar\joinrel\rightharpoonup}
\def\longlharpdn{\leftharpoondown\joinrel\relbar}
\def\rlPOON#1{\vcenter{\hbox{\ooalign{\raise2.3pt
        \hbox{$#1\longrharpup$}\crcr $#1\longlharpdn$}}}}
\def\eqbm{\mathrel{\mathpalette\rlPOON{}}\rm}
\def\eqbmlab#1_#2{\mathrel{\mathop{\eqbm}\limits~{#1}_{#2}}\rm}
\def\yields{\longrightarrow\rm}
\def\yieldslab~#1{\mathrel{\mathop{\longrightarrow}\limits~{#1}} \rm}


$$A\eqbm B$$
$$A\eqbmlab A_B$$
$$A\yieldslab~x$$
\bye
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\fontdimen17\twelvesymbolscript=2.65pt
