| http://www.w3.org/ns/prov#value | - such a direction to be actuated by the pumping of the fluid to move the device in one direction; a third cuppacker mounted on a third member and a fourth cup packer mounted on a fourth member adjacent said third member, said packers being faced in'such a direction as to be actuated by the pumping of the fluid to move the device in the other direction; an annular friction slide valve mounted for s
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