Abstract :
W. G. Taylor: Both cable-tool and rotary drilling impose extremely heavy duty on the power equipment, as is indicated to some extent by the graphic charts submitted in Mr. Murphy´s paper. It would be even more interesting if he had shown some records of the work required to handle and set the casing which lines the well. In fact, it is this work which really determines the size of motor necessary for cable-tool drilling. The work is fully as heavy as handling drill pipe in rotary drilling.
