Cooking vessel

Claim 1

A HEATING DEVICE COMPRISING A VESSEL HAVING A LAMINATED BOTTOM AND INTEGRALLY CONNECTED LAMINATED SIDE WALLS, SAID BOTTOM INCLUDING A FIRST PLANE METAL LAYER DEFINING A PLANE HEATING SURFACE AND A SECOND METAL LAYER GENERALLY COEXTENSIVE WITH SAID FIRST LAYER INTIMATELY MOLECULARLY BONDED TO SAID FIRST LAYER OVER THE MAJOR PORTION OF THE AREAS OF SAID LAYERS, A PORTION OF SAID LAYERS BEING SEPARATED TO DEFINE A CHAMBER BETWEEN SAID LAYERS WITH AN OPENING IN SAID SECOND LAYER AFFORDING ACCESS TO SAID CHAMBER, MEANS DEFINING A FIRST LOOPLIKE PASSAGEWAY BETWEEN SAID LAYERS WITH THE ENDS OF SAID PASSAGEWAY CONNECTED TO SAID CHAMBER, AN ELECTRICAL HEATING ELEMENT DISPOSED IN SAID PASSAGEWAY WITH THE ENDS THEREOF EXTENDING INTO SAID CHAMBER, A TEMPERATURE SENSING ELEMENT DISPOSED IN INTIMATE HEAT EXCHANGE RELATIONSHIP WITH SAID HEATING SURFACE SO AS TO BE RESPONSIVE TO THE TEMPERATURE THEREOF, AND ELECTRICAL MEANS OPERABLE SIMULTANEOUSLY WITH SAID HEATING ELEMENT IN DIRECT HEAT EXCHANGE RELATIONSHIP WITH SAID TEMPERATURE SENSING ELEMENT FOR ADDITIONALLY HEATING SAID TEMPERATURE SENSING ELEMENT.