1. IN AN ACETYLENE GENERATOR, A HOUSING, AN INNER DRUM IN SAID HOUSING, AN OUTER DRUM IN SAID HOUSING COAXIAL WITH SAID INNER DRUM AND SPACED OUTWARDLY THEREFROM THE AXIAL LENGTH OF SAID OUTER DRUM EXCEEDING THAT OF SAID INNER DRUM AND THE ENDS OF SAID OUTER DRUM EXTENDING BEYOND THE CORRESPONDING ENDS OF SAID INNER DRUM, MEANS FOR ROTATING SAID DRUMS, A CALCIUM CARBIDE HOPPER IN SAID HOUSING, MEANS FOR DELIVERING CALCIUM CARBIDE FROM THE BOTTOM OF SAID HOPPER INTO THE RECEIVING END OF SAID INNER DRUM, MEANS IN SAID INNER DRUM FOR MOVING MATERIAL FROM SAID RECEIVING END OF THE OPPOSITE END OF SAID INNER DRUM AS SAID INNER DRUM IS ROTATED, MEANS FOR DELIVERING WATER INTO SAID RECEIVING END OF SAID INNER DRUM, MEANS IN SAID OUTER DRUM FOR MOVING MATERIAL DELIVERED INTO SAID OUTER DRUM OPPOSITELY FROM THAT IN SAID INNER DRUM, WHEREBY MATERIAL DROPPING OFF FROM SAID OPPOSITE END OF SAID INNER DRUM ONTO SAID OUTER DRUM WILL THEN MOVE ALONG THROUGH SAID OUTER DRUM, A SCREEN FORMING A PORTION OF THE CYLINDRICAL WALL OF SAID OUTER DRUM NEAR THE END OF THE COURSE OF SAID MATERIAL IN SAID OUTER DRUM, WHEREBY FINE LINE PARTICLES RESULTING FROM GAS GENERATION WILL, UPON REACHING SAID SCREEN, DROP THROUGH SAID SCREEN INTO THE BOTTOM OF SAID HOUSING, AND A SERIES OF CUPS ON THE INSIDE OF SAID OUTER DRUM BEYOND SAID SCREEN, SAID CUPS PASSING ABOVE THE TOP OF SAID HOPPER WITH THE ROTATION OF SAID OUTER DRUM, WHEREBY MATERIAL WHICH HAS NOT BEEN COMPLETELY UTILIZED FOR GAS GENERATION WHEN REACHING SAID CUPS WILL BE RETURNED TO SAID HOPPER FOR RENEWED TRAVEL THROUGH SAID DRUMS.