During the Echo IV electron beam rocket flight, 114 moles of neutral N2 was injected for the attitude stabilization system. The interaction of the 40- kV 80-mA beam with this relatively dense cloud was studied as a 'gas plume' to enchance the flow of neutralizing return current to the rocket body. It was found found that the currents preferentially followed a route back through the region where the beam interacted with the N2. A complex luminous discharge was observed photometrically to accompany beam injection. This discharge was strongly roll modulated as the rotating beam swept through the injected gas near the rocket. The neutral N2 number density was measured by observing 3914-¿ emission produced by the beam impact, and reached nearly 1015 cm-3 at times. During a 1-s 40-kV 80-mA beam injection pulse the discharge became oscillatory and 'flickered' with a frequency near 22 Hz, somewhat lower than the N2+ ion gyrofrequency. The injected N2 on one occasion apparently acted as a fluorescent screen, and a photometric pulse was observed from a conjugate hemisphere beam echo. Ionospheric positive ions have been used to measure E¿B drifts by their flow pattern at rocket altitudes, but it was found that the N2 cloud interacted by collision to isotropize and thermalize the flow patterns, so electric fields could not be studied by this technique.