Time resolved measurement of shock pressures in high explosives is possible with inexpensive composite carbon resistors. These resistors are embedded plane to the surface of a Plexiglas slab fixed at the end of the explosive. This configuration was used with gap test experiments with a 10 g donor charge. No initiation delay is measured in Seismoplast I (plastic PETN) up to a gap height of 10 mm PMMA (Plexiglas) due to the time resolution of the measuring system. From 10 mm to 22.5 mm gap height distances for detonation development up to 25 mm are found. For even greater gap heights a shock wave with decreasing amplitude occurs. The detonation development can be explained by the measured structure of the shock waves. Behind a first shock front with nearly constant pressure a second front propagates with increasing pressure which at last catches up with the first and then the pressure increases further up to the Chapman‐Jouguet pressure of 160 kbar. At a gap height of 25 mm a stationary shock wave configuration with amplitudes of 20 kbar and 30 kbar was observed.

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The electrical conductivity of water was measured under shock loading by explosives. The experiments in the pressure range from 5 to 15 GPa were made with shock waves produced by cylindrical charges made of RDX/TNT 60/40. The higher pressures up to 40 GPa were reached by Mach reflection in a cylindrical tube of explosive filled with water. The results can be explained assuming that the electrical conductivity of water is caused by the autoionisation of the water molecules. Assuming furthermore that the autoionisation is only dependent on the shock temperature, the reaction energy can be computed to 94.6 kJ mol-1, in good agreement with experiments made by Franck with supercritical steam, which gave a result of 85.0 kJ mol-1.

The detonation velocity of rods made of RDX/TNT 60/40 was determined with high accuracy in the temperature range from 77 K to 338 K. It was found out that the detonation velocity decreases with increasing temperature. To explain this thermodynamically unusual behaviour it is assumed that the effect of the increase of the detonation velocity with increasing temperature is superposed on the decrease caused by the simultaneous decreasing density of the explosive.