  We consider scalar perturbations in the time-dependent Ho\u{r}ava-Witten
Model in order to probe its stability. We show that during the non-singular
epoque the model evolves without instabilities until it encounters the
curvature singularity where a big crunch is supposed to occur. We compute the
frequencies of the scalar field oscillation during the stable period and show
how the oscillations can be used to prove the presence of such a singularity.
