| abstract |
A container for containing a liquid has a single opening through which extends a porous wick. The wick extends into the liquid. A portion of the wick extends out of the container through a tubular shield and a generally annular electric heater. The heater is movable between a first position, where the shield is disposed between the heater and the wick, and a second position, where the shield is not so disposed, so as to enable a supply of heat from the heater to the wick to be regulated. |