  The CLEO III Ring Imaging Cherenkov detector uses LiF radiators to generate
Cherenkov photons which are then detected by proportional wire chambers using a
mixture of CH$_4$ and TEA gases. The first two photon detector modules which
were constructed, were taken to Fermilab and tested in a beam dump that
provided high momentum muons. We report on results using both plane and
"sawtooth" shaped radiators. Specifically, we discuss the number of
photoelectrons observed per ring and the angular resolution. The particle
separation ability is shown to be sufficient for the physics of CLEO III.
