  Abraham's force seems to have been observed in very low frequency
experiments, but the existence of an Abraham's force exerted by light is still
to be proved. Twenty years ago Brevik proposed an experiment for checking what
forces light exert in the interior of a transparent medium. It is argued that
his proposal is feasible today with a detection method now at hand, thanks to
the great improvements achieved in manufacturing optical fibres with the
required physical properties.
