The unique trumpet-shaped water spouts found in Southwestern architecture originally served to throw water clear of moisture-susceptible adobe walls; the radial vanes provided both reinforcement and decoration. Because traditional adobe is not fired, but merely dried in the sun, it cannot be allowed to become saturated with water or it will quickly return to its natural state--mud. At the height of adobe’s popularity during the 1920s, a number of manufacturers strove to improve adobe’s weatherability; the Bitadobe process, for example, mixed adobe clay with bitumen (a product of oil refining) to yield an ostensibly waterproof brick. Ultimately, the effort was moot, since Revival styles had fallen out of favor by the mid-Thirties.