Project 1.1d of Operation UPSHOT-KNOTHOLE measured dynamic pressures in the shock wave and preshock pressures. It also conducted a feasibility study of new and modified gages to measure dynamic pressure, density, temperature, and particle velocity. Measured dynamic pressures can be compared with those calculated from the measured overpressures using the Rankine-Hugoniot shock relations and regular reflection theory. When no precursor is formed, measured dynamic pressures are in reasonable agreement with those calculated although some effects of thermal and mechanical interaction are noted. Dynamic pressures measured in the precursor are much higher than those calculated. Laboratory tests have indicated that the end instrument used does respond to dust as well as to air, and the quantity measured by these gages is apparently 12 rho u-squaredair rho u-squareddust when dust is present in the shock wave, as is true in the precursor. Measurements have shown a few instances of real but small preshock increases in air pressure, all apparently caused by thermal radiation alone.