The scarcity of imported materials, together with a lack of skilled laborers, compelled the Fathers to employ simple building materials and methods in the construction of mission structures. Since importing the quantity of materials necessary for a large mission complex was impossible, the padres had to gather the materials they needed from the land around them. Five basic materials we used sexucting the permanent mission structures: adobe, timber, stone, brick, and tile. "Adobes" (mud bricks) were made from a combination of earth and water, with chaff, straw, or manure added to bind the mixture together. Occasionally pieces of bricks or shells were placed in the mix to improve the cohesiveness. The soil used may have been clay, loam, or sandy or gravelly earth. The making of the bricks was a simple process, derived from methods originally developed in Spain and Mexico. A convenient, level spot was chosen near the intended building site and close to a suitable water supply (usually a spring or creek). The ground was dug up and soaked with water, whereupon bare-legged workers would stomp the wet earth and binders into a consistency fit for carrying to, and placing in, the brick molds.