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Show A SOLAR BAKERY Dr. Charles G. Abbott puts the sun to work for him heating a solar stove. It bakes bread readily. ' Dr. Abott states: "after the sun goes down the temperature inside the oven will drop slowly uuiing the night, but there is still ample heat to broil bacon and bake biscuits in the morning." Dr. Abbott has also arranged a solar hot water heater by coiling 150 feet of garden hose on the cottage roof. It heats five gallons of water at a time except in cloudy weather, when it is of little use. The sun stove works in this way: Upon the glass covered top of a trough shaped "furnace" "fur-nace" sunlight falls. An ordinary -clock mechanism keeps the face of the furnace toward the sun. Because of the curvature of the trough, light is brought to a focus along a copper tube and extends ex-tends lengthwise through the furnace. The tube is surrounded by a large tube of special glass, thermos-bottle fashion, the space between the tubes being a vacuum. The inner tube is filled with heavy machine oil, which does not boil at ordinary furnace heat. When heated by the focussed rays of the sun, the oil rises and circulates cir-culates around three sides of the oven, which looks something like . a sawed-off water tower. Leaving from 300 to 400 degrees of heat in the oven, the cooled oil gravitates back into the furnace to be recharged again, and thus a lazy circulation of about 60 gallons i is automaticaly maintained. Except for leakage, the oil lasts indefinitely." in-definitely." N. Y. Sun. I o . |