I've gotten many questions on this, so try to answer in one posting. I am a woodworker and have studied many incubators from the 1900 - 1940's. This incubator was a proto-type of a Buc keye Bantam model. The cabinate was constructed of hardwood, this in a full 1 1/2" thick. Heating is acomplished from a copper heating system that is fill with water. Outside the incubator is a copper boiler that heats the water. By convection, the heated water is circulated within the cabinet. There is a rubber bar (I used Nylon) inside that expands as the temp goes up (Thermal Expansion)that moves the mechanism outside. The arm hold a damper which covers the flue of the boiler for maximum heating of the water. As the rubber bar expands, it moves the arm that is counter-weighted to lift the damper off the flue, which then allows the lamp heat to escape out, thereby cooling the water. As the water cools, the rubber bar contracts, which again lowers the damper to heat water again. At end of bar, there is a adjustment knob to control temp. This incubtor works very well, and temperature is surprisingly constant and uniform within the cabinet. I believe it is better that electric, because it takes awhile for water to cool and therby reducing the ups and downs of a heated ekectric element!. I hope that I was able to answer your questions. No, I do not have this machine anymore, I sold it last month.
