  The torsional oscillator experiments described here examine the effect of
disorder on the non-classical moment of inertia (NCRI) of a solid 4He sample.
The NCRI increases with increasing disorder, but the period changes responsible
for this increase occur primarily at higher temperatures, while at the lowest
temperature the oscillator period remains relatively unaffected. This result is
contrary to expectations based on a supersolid scenario and points to a
non-superfluid origin for the NCRI.
