From 1860 to 1900, the cable tool method was used extensively. This method uses a heavy steel bar and bit attached to the bottom of a cable. The bottom assembly is dropped rhythmically against the bottom of the hole to crush and chip away at rock formations. Periodically, drilling is stopped and special tools are lowered to the bottom to clean out the cuttings. Prior to 1900, several wells exceeded 2000 ft, and in 1953, one well was drilled to 11,000 ft using the cable tool method.