Paper drying machine

Claim 1

A HOOD FOR APPLYING AIR ON A ROLL AND HAVING A GENERALLY ARCUATE SURFACE TO EXTEND AROUND THE ROLL AT AN APPROXIMATELY UNIFORM DISTANCE THEREFROM, SAID HOOD INCLUDING MEANS DEFINING A PLURALITY OF AIR CONDUCTING PLENUM CHAMBER IN THE HOOD WHICH EXTEND LONGITUDINALLY OF THE ROLL AND WHICH HAVE WALLS FACING THE ROLL AND DEFINING SAID ARCUATE SURFACE AND ALSO HAVE SIDE WALLS, SAID SIDE WALLS OF ADJACENT ONES OF SAID PLENUM CHAMBERS BEING SUBSTANTIALLY EQUALLY SPACED AND DEFINING AIR EXHAUST PASSAGES THEREBETWEEN, SAID ROLL FACING WALLS BEING PROVIDED WITH ROWS OF OPENINGS THERETHROUGH EXTENDING LONGITUDINALLY OF THE ROLL AND INCLUDING TWO SIDE ROWS FOR EACH OF SAID PLENUM CHAMBER ADJACENT THE OPPOSITE SIDES OF THE PLENUM CHAMBER AND INCLUDING ALSO AT LEAST ONE ADDITIONAL INTERMEDIATE ROW, EACH OF SAID ROWS IN EACH OF SAID ROLL FACING WALLS BEING SPACED A PREDETERMINED DISTANCE APART ARCUATELY OF THE ROLL AND SAID PLENUM CHAMBERS BEING SO CLOSELY DISPOSED TO EACH OTHER THAT THE ADJACENT SIDE ROWS OF ADJACENT ONES OF SAID PLENUM CHAMBERS ARE ALSO SPACED SUBSTANTIALLY THE SAME DISTANCE APART AS THE ROWS IN EACH OF SAID ROLL FACING WALLS AND THE OPENINGS IN IMMEDIATELY ADJACENT ONES OF SAID LONGITUDINAL ROWS BEING STAGGERED AND SO LOCATED WITH RESPECT TO EACH OTHER THAT THE OPENINGS LIE ON LINES EXTENDING HELICALLY AROUND THE ROLL SO AS TO APPLY JETS OF AIR FROM SAID CHAMBERS ON THE SURFACE OF THE ROLL WHICH ARE SUBSTANTIALLY UNIFORMLY SPACED BOTH LONGITUDINALLY OF THE ROLL AND ALSO ARCUATELY OF THE ROLL.