The Bechers' industrial vision has become an essential part of the way we see today; their head-on, deadpan photographs of pithead gear and water towers and blast furnaces have for more than 30 years expressed a serenely cool, rigorous approach that reduces the individual structures they photograph to variations on an ideal form. In this, their latest work, the Bechers' present four principally different forms of gas holders or gas tanks in 140 photographs taken during the years 1963-1992 in Great Britain, France, Belgium, Germany, and the United States. The subjects are photographed under overcast skies that eliminate expressive variations in lighting; the Bechers make no attempt to analyze or explain them. Captions contain only the barest of information: time and place. On the subject of gas holders, the Bechers limit their remarks to a minimal functional description, leaving the esthetic dimension of their subject to the photographs themselves: much of the fascination of these photographs lies in the fact that these unadorned metallic structures, presumably built with little concern for their visual impact, are almost invariably striking in appearance. Bernd and Hilla Becher teach at the DÜsseldorf Art Academy. They began their collaborative photographic enterprise in 1957, when they did a study of workers' houses in their native Germany. The Bechers follow in a distinguished line of German photographers that includes August Sander, Albert Renger-Patzsch, and Werner Manz, all of whom contributed in different ways to the definition of "objective" photography.