In this paper a review is given of the main experimental results obtained with the Sceptre IV discharge. The torus was toroidally machined from high quality copper and has an initial magnetic field accurately matched to the tube wall. With capacitor bank energies up to 106 J, discharge currents up to 500 kA have been studied. Many of the properties of the discharge, including the electron temperature, the average magnetic field profiles and the fusion reaction rates are similar to those obtained with other experiments (Zeta, Sceptre III), there being no appreciable change in these properties with either the improved geometrical shape or with the increase in energy. Differences from the earlier experiments include larger magnetic field fluctuations, less reproducibility, somewhat lower ion temperatures (Doppler broadening) and a different radial profile for the ion temperature. These differences are possibly due to the magnetic fields generated at the gaps by eddy currents when the gas current is flowing. New measurements include a study of the θ as well as motion of the reacting deuterons, and a new method of measuring the electron temperature. A summary is given of the theories which have been put forward to explain the electron energy loss, the positive ion heating and the magnetic field profiles.