Boiling water atomic reactor

Claim 1

IN A WATER COOLED NUCLEAR REACTOR, A TANK, A PLURALITY OF SHEATHS DISPOSED AXIALLY IN SAID A TAND FUEL BARS IN SAID SHEATHS, A LOWER GRATE IN SAID TANK SUPPORTING SAID SHEATHS, A COOLING WATER INLET IN SAID TANK BELOW SAID LOWER GRATE, AN UPPER GRATE IN SAID TANK SUPPORTING THE UPPER ENDS OF SAID SHEATHS, WATER OUTLETS IN SAID TANK BENEATH SAID UPPER GRATE, A TACK EXTENDING FROM THE UPPER END OF EACH OF SAID SHEATHS, MEANS ON EACH OF SAID STACKS FOR DOWNWARD DISCHARGE OF DROPS OF COOLING WATER, VAPOR OUTLETS IN SAID TANK ABOVE SAID MEANS, A THERMAL SHIELD IN SAID TANK SPACED THEREFROM AND SURROUNDING SAID STACKS AND IN FLUID TIGHT ENGAGEMENT WITH SAID UPPER GRATE, A PERFORATE SCREEN SPACED FROM AND WITHIN SAID SHIELD SURROUNDING SAID STACKS AND SUPPORTED ON SAID UPPER GRATE WHEREBY A COMPARTMENT IS PROVIDED BETWEEN SAID SHIELD, SAID SCREEN AND SAID UPPER GRATE TO RECEIVE COOLING WATER, THE FLOW OF COOLING WATER FROM AROUND SAID STACKS THROUGH SAID SCREEN TO THE COMPARTMENT BEING RETARDED BY SAID SCREEN THEREBY MAINTAINING A HIGHER WATER LEVEL AROUND SAID STACKS THAN IN THE COMPARTMENT.