  We demonstrate a technique for continuous tuning of the Hanle effect from
electromagnetically induced transparency (EIT) to electromagnetically induced
absorption (EIA) by changing the polarization ellipticity of a control beam. In
contrast to previous work in this field, we use spatially separated probe and
control beams. The experiments are done using magnetic sublevels of the $ F_g =
4 \rightarrow F_e = 5 $ closed hyperfine transition in the 852 nm D$_2$ line of
$^{133}$Cs. The atoms are contained in a room temperature vapor cell with
anti-relaxation (paraffin) coating on the walls. The paraffin coating is
necessary for the atomic coherence to be transported between the beams. The
experimental results are supported by a density-matrix analysis of the system,
which also explains the observed amplitude and zero-crossing of the resonances.
Such continuous tuning of the sign of a resonance has important applications in
quantum memory and other precision measurements.
