UNOFF and other phenomena associated with heavy rains during the winter of I937-I938 produced many significant changes in the landscape of southern California. The rainfall was especially heavy in the period February 28-March 3, I938, when 712 inches of rain fell; at Ventura 4 inches fell in 24 hours on March 2 and 3. Landslides were set in motion, and great quantities of material in areas of weathered bedrock were moved by earthflows. The Ventura slides are unusually interesting for their effect on human activities and are especially important in the oil field, where they have destroyed wells, buckled pipe lines, and shifted roads.