  We report the results of the analyses of the cosmic ray data collected with a
4 tonne (3$\times$1$\times$1~m$^3$) active mass (volume) Liquid Argon
Time-Projection Chamber (TPC) operated in a dual-phase mode. We present a
detailed study of the TPC's response, its main detector parameters and
performance. The results are important for the understanding and further
developments of the dual-phase technology, thanks to the verification of key
aspects, such as the extraction of electrons from liquid to gas and their
amplification through the entire one square metre readout plain, gain
stability, purity and charge sharing between readout views.
