The dynamics of complex polynomials and automorphisms of the shift

An incinerator including a combustion chamber is provided wherein an expansion grate is disposed proximate the entrance to the combustion chamber. The expansion grate is movable between an extended position in which the amount of combustible materials which may be deposited within the incinerator is limited and a retracted position in which the combustible materials fall to the bottom of the combustion chamber for incineration. The incinerator also includes a mechanically interconnected loading door and combustion chamber access cover. When it is desired to load the combustion chamber with combustible materials, the expansion grate is placed in its extended position and the loading door and access cover are opened. As long as the expansion grate is not retracted, the loading door and access cover may be opened repeatedly to deposit more combustible materials. However, when the expansion grate is retracted, an interlock means and locking means combine to keep the loading door locked until an incineration cycle is completed. Thus, it is impossible to overload the combustion chamber with combustible materials or to open the loading door during the incineration cycle.