  The cosmology of the Horava-Witten M-Theory reduced to five dimensions
retaining the volume modulus is considered. Brane matter is considered as a
perturbation on the vacuum solution, and the question of under what
circumstances does the theory give rise to the standard RWF cosmology is
examined. It is found that for static solutions, one obtains a consistent
solution of the bulk field equations and the brane boundary conditions only for
pure radiation on the branes. (A similar result holds if additional 5-branes
are added in the bulk.) If one stabilizes the fifth dimension in an ad hoc
manner, a similar inconsistency still occurs (at least for a Hubble constant
that has no dependence on y, the fifth dimension.) Within this framework, the
possibility of recovering the RWF cosmology still remains if the volume modulus
and /or the distance between branes becomes time dependent, under which
circumstances the Hubble constant must then depend on y (unless the fifth
dimension and volume modulus expand at precisely the same rate).
