  Recently we have shown that $YbInCu_4$ and related compounds present a solid
state Pomeranchuk effect. These systems have a first order volume transition
where a local moment phase coexists with a renormalized Fermi liquid in analogy
with $^3He$ at its melting curve. We demonstrate here experimentally that the
solid state Pomeranchuk effect, controlled by a magnetic field, can be used to
produce cooling.
