Blades for fluid flow machines

Claim 1

A BLADE ADAPTED FOR USE IN A FLUID FLOW MACHINE, SAID BLADE HAVING ROOT AND TIP ENDS, LEADING AND TRAILING EDGES AND FLUID DIRECTING FACES, SAID BLADE ALSO HAVING OPPOSED INTERIOR WALLS DEFINING AN INTERNAL PASSAGEWAY EXTENDING LONGITUDINALLY OF AND ADJACENT ONE OF SAID EDGES, SAID BLADE HAVING A COOLING FLUID SUPPLY DUCT ADAPTED TO BE SUPPLIED WITH COOLING FLUID AND IN COMMUNICATION WITH SAID INTERNAL PASSAGEWAY SOLELY IMMEDIATELY ADJACENT THE MID-HEIGHT OF THE BLADE FOR DIRECTING A SINGLE STREAM OF COOLING FLUID AGAINST THE WALL OF SAID PASSAGEWAY ADJACENT SAID ONE EDGE, THE COOLING FLUID THEREAFTER FORMING A LONGITUDINAL FLOW THROUGH SAID PASSAGEWAY, SAID INTERNAL PASSAGEWAY HAVING AT LEAST ONE OUTLET AT A POINT REMOTE FROM THE COMMUNICATION OF SAID INTERNAL PASSAGEWAY WITH SAID COOLING FLUID SUPPLY DUCT, A PLURALITY OF BARS EXTENDING ACROSS SAID PASSAGEWAY AT RIGHT ANGLES TO THE MID-CHORD LINE OF THE BLADE, EACH OF SAID BARS BEING INDIVIDUALLY SUPPORTED IN SAID PASSAGEWAY AT ITS ENDS ONLY BY THE RESPECTIVE OPPOSED INTERIOR WALLS OF THE PASSAGEWAY, SAID BARS BEING ARRANGED IN A PLURALITY OF CHORDWISE EXTENDING ROWS SPACED PROGRESSIVELY DOWNSTREAM OF ONE ANOTHER RELATIVE TO THE LONGITUDINAL FLOW OF THE COOLING FLUID THROUGH SAID PASSAGEWAY, THE BARS OF EACH OF SAID ROWS BEING STAGGERED WITH RESPECT TO THE BARS OF THE IMMEDIATELY PRECEDING ROW SO AS TO PRODUCE SUBSTANTIAL TURBULENCE IN THE LONGITUDINAL FLOW OF COOLING FLUID AS IT FLOWS THROUGH SAID PASSAGEWAY, AND SAID ROWS OF BARS ADJACENT THE MIDHEIGHT OF THE BLADE BEING MORE CLOSELY SPACED THAN THE ROWS OF BARS POSITIONED ELSEWHERE IN SAID PASSAGEWAY.