Experiments are described in which a shock‐tube facility was used for the determination of the Hugoniot equation of state of granite. The facility was operated in two modes. Very low stress levels&sgr;[over equal to less-than]0.2 kbarswere obtained by allowing an air shock wave to impinge directly upon a sample material. Higher stresses,&sgr;[over equal to less-than]50 kbars, were obtained when the incident air shock wave was used to accelerate a metal projectile which then impacted upon the sample at a desired velocity. The instrumentation and data‐reduction methods are discussed and the resulting Hugoniot points for granite below and in the neighborhood of its dynamic elastic limit are given.