Abstract: The velocity of sound at the time of 100-ton shot at Trinity was measured to be 1116.1 ft/sec. Values of blast pressure computed from the excess velocity are given, but are not considered as reliable.
From abstract: "A chamber was constructed with three electrodes dividing the space into two regions of 800 c.c. The surfaces of one of these were coated with boron carbide. With opposite potentials on two electrodes, ion currents to the collecting electrode due to gamma rays were practically cancelled and ion currents due to alpha rays induced by slow neutrons were measured."