Fishtail Bit

The first rotary drill for oil production was invented in 1845. Rotary drilling revolutionized the petroleum industry after the 1901 discovery of oil at Spindletop Hill in Texas launched a drilling boom.

The fishtail bit was an early type of rotary drill bit used for drilling oil. The name came from its flat, chisel-like shape, resembling a fish tail. The fishtail bit was the primary rotary bit in Texas until the 1930s. It worked very well in the softer soil formations on the coast; however, it did not do well in harder rock formations found further inland. The fishtail was replaced by more efficient bit designs, notably the two-cone roller bit that was first introduced in 1909.