  Specific-heat measurements are reported near the Curie temperature ($T_C$~=
320 K) on tri-glycine sulfate. Measurements were made on crystals whose
surfaces were either non-grounded or short-circuited, and were carried out in
magnetic fields up to 9 T and electric fields up to 220 V/cm. In non-grounded
crystals we find that the shape of the specific-heat anomaly near $T_C$ is
thermally broadened. However, the anomaly changes to the characteristic sharp
$\lambda$-shape expected for a continuous transition with the application of
either a magnetic field or an electric field. In crystals whose surfaces were
short-circuited with gold, the characteristic $\lambda$-shape appeared in the
absence of an external field. This effect enabled a determination of the
critical exponents above and below $T_C$, and may be understood on the basis
that the surface charge originating from the pyroelectric coefficient, $dP/dT$,
behaves as if shorted by external magnetic or electric fields.
