Hydraulically operated earth boring tools

Claim 1

IN EARTH BORING APPARATUS, A MAST HAVING A PAIR OF LONGITUDINALLY EXTENDING TRANSVERSELY SPACED HYDRAULIC CYLINDERS FORMING A PAIR OF LEGS THEREOF, SAID MAST HAVING A SECOND PAIR OF LEGS TRANSVERSELY SPACED SUBSTANTIALLY EQUIDISTANTLY FROM EACH OTHER AND FROM SAID CYLINDERS, TRANSVERSE FRAME MEMBERS CONNECTING EACH OF SAID CYLINDERS WITH ONE OF SAID LEGS OF SAID SECOND PAIR AT THE ENDS THEREOF AND AT SPACED POINTS BETWEEN SAID ENDS, A PISTON IN EACH OF SAID CYLINDERS, A ROD EXTENDING FROM EACH PISTON THROUGH THE UPPER END OF THE CYLINDER HAVING SAID PISTON, CLOSURE MEANS AT THE UPPER ENDS OF SAID CYLINDERS EACH HAVING AN OPENING SLIDABLY RECEIVING ONE OF SAID RODS, MEANS PROVIDING A FLUID TIGHT JOINT BETWEEN SAID RODS AND CLOSURE MEANS, MEANS FOR SUPPLYING HYDRAULIC FLUID TO SAID CYLINDERS ADJACENT THE OPPOSITE ENDS THEREOF, AN ELONGATED TUBULAR MEMBER OF APPROXIMATELY THE LENGTH OF SAID ROD EMBRACING EACH OF SAID CYLINDERS AND DETACHABLY SECURED AT THE UPPER END THEREOF TO THE UPPER END OF ONE OF SAID RODS TO MOVE THEREWITH, A PLATFORM SECURED