1. IN AN INSULATED RAILROAD TANK CAR FOR HANDLING AND TRANSPORTING MATERIALS UNDER OTHER THAN AMBIENT TEMPERTURE CONDITIONS AND WHEREIN THE TANK CAR INCLUDES AN ELONGATED AND ENCLOSED COMMODITY CONFINING TANK SHELL, A PAIR OF RAILROAD CAR BODY BOLSTER AND STUB STILL ASSEMBLIES FOR SUPPORTING THE OPPOSITELY DISPOSED ENDS OF SAID TANK SHELL, AND AN OUTER HOUSING THAT FORMS AN ENCLOSURE FOR AND EFFECTS THE CONFINEMENT OF AN INSULATING LAYER THAT SUBSTANTIALLY ENTIRELY SURROUNDS SAID TANK SHELL EXCEPT IN THE REGIONS ADJACENT THE LOWER SURFACE OF THE EXTREMITIES OF SAID TANK SHELL WHEREAT SAID TANK SHELL IS JOINED TO SAID ASSEMBLIES; AN COMBINED INSULATING AND DISCHARGING MEANS, SAID INSULATING AND DISCHARGING MEANS, SAID INSULATING AND DISCHARGING MEANS COMPRISING A PAIR OF SUPPORT STRUCTURES, ONE EACH OF SAID SUPPORT STRUCTURES BEING JOINTED TO THE INTERIOR SURFACE OF SAID TANK SHELL IN CONFINING RELATION SHIP RELATIVE TO THE LOWER INNER SURFACE OF ONE EACH OF SAID TANK SHELL EXTREMITIES ADJACENT THE LOCATION WHEREAT SAID SHELL IS JOINTED TO SAID ASSEMBLIES; A PAIR OF PLATE MEMBERS, ONE EACH OF SAID PLATE MEMBERS BEING SECURED TO ONE EACH OF SAID SUPPORT STRUCTURES SO AS TO DEFINE A FULLY ENCLOSED HOUSING FOR INSULATING MATERIAL; AND INSULATING MEANS INTIMATELY CONFINED WITHIN SAID ENCLOSURES DEFINED BY SAID PLATES AND THE ADJACENT LOWER INNER SURFACE OF SAID TANK SHELL.