In the ancient world, Arabs mixed sand, clay, water, and a vegetal binding material to make al-tob. The Spanish, principally because of contact with the Arabic Moors of North Africa, knew the process and called it adobe. When they arrived in the New World, the Spanish colonists found that the Indians in the Southwest had been using the same process for centuries. Today, we still know it by its Spanish name: adobe.

It is not surprising that the Spanish and Indians shared an affinity for building with adobe. The basic materials used to make it were common to both continents. In addition, it had unique qualities that made it an ideal building ...