In the history of building, the word "concrete" has been used to describe a myriad of concoctions, some of which are hardly related, very few of which resemble the particular agglomeration of materials we know today as "concrete." As is the case now, concrete has always been an experimental material: hailed as a panacea, only to be disowned as the ill-begotten child of madness or ignorance. Aside from sporadic periods of popularity and experimentation, concrete has been the choice of necessity for many centuries, particularly in utilitarian structures, for its advocates have always espoused its economy, durability and flexibility. A "choice of necessity" cannot be separated from what Iwould call a "choice of opportunity," for in each instance, the manifestation of concrete as an important building material cannot be separated from the natural resources and the skill of the labor at hand to give the material form. What has emerged from the series of apparent abberations and mutations is instead relatively continuous technological evolution, one form of which has perhaps ended with the concrete era of Sequin; Texas in the mid-nineteenth century. / text