Thrallbr/Williamson County, Texasbr/30 35.390' N 97 17.919' W br/br/Text: An 1876 International amp; Great Northern railroad siding called "Stiles Switch" for landowners J. E. and F. M. Stiles, grew into a shipping point for the Swiss and Germans who settled in this area. The post office that opened in 1901 was named for Methodist minister and historian Homer S. Thrall. Nearly oil discoveries and sudden growth caused the town to be incorporated in 1915. The 38.21-inch rainfall of Sept. 8-9, 1921, gave Thrall a world record. Since 1961, Texas Aamp;M University agricultural research center had operated here. Farming remains the basic local industry.