Most particle accelerators have been built to perform certain predesignated tasks, sometimes to assist physicists in unfolding nuclear structure or to generate yet a new genus of particles. There is no exception to this convention relative to the special purpose accelerator at the Los Alamos Scientific Laboratory. PHERMEX was designed and built not bv nuclear physicists but by a group whose inherent professional interests lie in fluid dynamics,chemical kinetics, and extreme states of matter. These interests have maintained the rigid objectives and provided the purpose and drive to complete this program successfully. PHERMEX is now operating, performing admirably the tasks for which it was designed. Therefore, perhaps it is time to say more about why this machine was built, how it was built, and what is being done with it today. PHERMEX, a Pulsed High‐Energy Radiographic Machine Emitting X Rays, designed and built by members of the staff of the Los Alamos Scientific Laboratory, is a high‐current standing‐wave linear accelerator which generates intense bursts of x rays for flash radiographic studies of explosive‐driven metal systems. A brief discussion is presented of the need for this device and of some of its design features, operational parameters, and radiation output. Several radiographs are shown which illustrate typical applications to studies of fluid flow. A detailed report (“A Pulsed High‐Energy Machine Emitting X Rays” by T. J. Boyd, B. T. Rogers, F. R. Tesche, and D. Venable) is to be published elsewhere.