We report on the initial results from a measurement of the anti-neutrino flux and spectrum at a distance of about 800 m from the three reactors of the Palo Verde Nuclear Generating Station using a segmented gadolinium-loaded scintillation detector. We find that the anti-neutrino flux agrees with that predicted in the absence of oscillations excluding at 90% CL anti-ne - anti-nx oscillations with Dm2 > 1.12 x 10-3 eV2 for maximal mixing and sin2 2q > 0.23 for large Dm2 .