Laboratory furnace

Claim 1

AN ELECTRICALLY HEATED LABORATORY FURNACE FOR A CRUCIBLE AND THE LIKE COMPRISING, IN COMBINATION, A REFRACTORY HEATER BLOCK, A SUBSTANTIALLY FLAT AREA RESISTANCE HEATER ELEMENT CARRIED BY THE TOP OF SAID HEATER BLOCK, A REFRACTORY BLOCK COMPRISING AN OPEN-TOPPED HEATING CHAMBER HAVING AN UNOBSTRUCTED CYLINDRICAL VERTICAL WELL THEREIN EXTENDING THERETHROUGH, SAID HEATING CHAMBER BEING ADAPTED TO BE CARRIED BY SAID HEATER BLOCK IN CENTRAL RELATION THERETO AND TO SAID HEATER ELEMENT WITH THE BOTTOM OF SAID WELL AND AT LEAST THE PORTION OF THE UNDERSIDE OF SAID HEATING CHAMBER IMMEDIATELY AROUND SAID WELL BEING DIRECTLY ABOVE SAID HEATING ELEMENT, A HOLDER FRAME ADAPTED TO REST ON THE UPPER PORTION OF SAID HEATING CHAMBER SPACED OUTWARDLY OF THE UPPER EDGE OF SAID WELL, AND A SUPPORT DEPENDING FROM SAID FRAME FOR A CRUCIBLE ADAPTED TO BE LOWERED INTO AND RAISED FROM SAID WELL.