II. Read and translate the text drilling and completing wells

Early wells were drilled with impact-type tools in a method called cable-tool drilling, in which a chisel-like bit was suspended from a cable to a lever at the surface, and an up-and-down motion of the lever caused the bit to pound the bottom of the hole and chip away the rock. Such drilling had to be interrupted periodically to allow loose rock chips to be removed with a basket-like device on the cable. Also, the well had to be free of liquids during the drilling process so that the bit could effectively remove rock. These necessarily dry holes allowed oil and gas to flow to the surface in large quantities as soon as a producing formation was penetrated. This created the image of a «gusher» as a successful well. Often, a large amount of oil was wasted before the well could be capped and brought under control.