Spindletop, near Beaumont, Texas, is a hill formed by a giant underground dome of salt that slowly made its way to the surface. The land feature became famous after oil was reached there in 1901. The surrounding area is not the solid material that oil drillers prefer; it is pure sand. The sand makes it difficult to drill, and when they found oil, the sand usually caved in on the hole. Driller Curt Hamill came up with the idea that they could put mud into the hole to keep the sand from being so soft. After the first try, the technique became the standard for preventing drilled holes from caving in. Several attempts had been made to find oil at Spindletop without success. In late 1900, a group headed by Captain Anthony F. Lucas made another attempt. On January 10, 1901, at a depth of 1140 feet, they struck oil. The oil blew the drilling equipment out of the well and gushed to a height well above the derrick. It took nine days to bring it under control. Beaumont immediately became an oil boom town, with its population tripling from 10,000 to 30,000. Many new wells were drilled, and among the businesses that were set up to handle the oil production were the forerunners of Gulf Oil, Amoco, and Humble Oil Company (later part of Exxon). With so many wells being drilled, production soon began to decline. However, in 1925, a new discovery at greater depth led to the peak production in 1927 of 21 million barrels. Thereafter, Spindletop went into decline and oil production ended in 1936. The heritage of the Spindletop boom era is maintained at the Spindletop-Gladys City Boomtown Museum in Beaumont.