1. A REINFORCED, THIN SHELLED RAILROAD TANK CAR WHICH COMPRISES IN COMBINATION AN ENCLOSED SELF-SUPPORTING HORIZONTALLY DISPOSED CYLINDRICAL TANK SHELL; SAID TANK SHELL HAVING AN ELONGATED CENTRAL SECTION ENCLOSED BY REINFORCED END WALLS; A PAIR OF REINFORCING BASE PLATES; ON EACH OF SAID REINFORCING BASE PLATES BEING SECURED TO THE UNDERSIDE OF SAID TANK SHELL ADJACENT ONE EACH OF SAID END WALLS AND EXTENDING BENEATH ONLY A PORTION OF THE EXTREMITIES OF SAID ELONGATED CENTRAL SECTION; A PAIR OF SHORT DRAFT SILL AND WHEEL ASSEMBLY STRUCTURES; ONE EACH OF SAID DRAFT SILL AND WHEEL ASSEMBLY STRUCTURES BEING SECURED TO ONE EACH OF SAID BASE PLATES ADACENT THE EXTREMITIES OF SAID ELONGATED CENTRAL SECTION OF SAID TANK SHELL; A PAIR OF TANK SHELL SUPPORTING CRADLE STRUCTURES; ONE EACH OF SAID CRADLE STRUCTURES BEING SECURED TO ONE EACH OF SAID BASE PLATES AND TO ADJACENT PORTIONS OF THE OUTER PERIPHERAL SURFACE OF SAID ELONGATED TANK SHELL CENTRAL SECTION SO AS TO PROVIDE SPACED APART SUPPORTS FOR THE END PORTIONS OF SAID TANK SHELL; A PAIR OF SURGE ARRESTING PLATE MEMBERS SECURED IN ANGULARLY DISPOSED RELATION RELATIVE TO THE INNER WALL SURFACES OF SAID TANK SHELL ADJACENT THE ENDS THEREOF; ONE EACH OF SAID PLATE MEMBERS BEING JOINED TO ONE EACH OF SAID END WALLS SO AS TO EXTEND BETWEEN THE INNER SURFACE OF SAID TANK SHELL AT A LOCATION INWARDLY OF THE SURFACE OF SAID TANK SHELL AT A LOCATION INWARDLY OF THE OUTER TERMINATION POINT OF SAID CORRESPONDING REINFORCING BASE PLATE; AND A PAIR OF REINFORCING RINGS; ONE EACH OF SAID REINFORCING RINGS BEING SECURED TO SAID ELONGATED CENTRAL TANK SHELL SECTION IN CONCENTRIC RELATION THEREWITH AND IN SUBSTANTIAL ALIGNMENT WITH THE INNER TERMINATION POINTS OF ONE EACH OF SAID BASE PLATES; SAID ANGULARLY DISPOSED SURGE ARRESTING PLATE MEMBERS FUNCTIONING POINT OF SAID SURGE LOADS INWARDLY OF THE OUTER TERMINATION POINT OF SAID REINFORCING BASE PLATES SO AS TO MINIMIZE STRESS FORCES NORMALLY INPARTED TO SAID TANK SHELL AT THE LOCATION AND SAID REINFORCING RINGS FUNCTIONING TO STIFFEN THE TANK SHELL ADJACENT THE INWARDMOST END PORTIONS OF EACH OF SAID REINFORCING BASE PLATES SO AS TO PROVIDE A RESISTIVE FORCE TO DEFLECTION OF THE INNERMOST ENDS OF SAID REINFORCING BASE PLATES.