I have the original furnace that was put in my bungelow when it was originally constructed in 1919. I believe it was originally a coal furnace and was coverted to oil and, during the 50's to natural gas. It is a "gravity" gas furnace. <br> <br>It is labeled "Excelcior Furnace Company, Chicago Illinois." <br> <br>Does any one have any information about this company or these furnaces? <br> <br>