Question: I recently went on an archaeological dig at Tyler State Park in Pennsylvania with my fifth grade Humanities class. I have to research one of the artifacts I found and was hoping you might know something about it. I went to a gas station and they said it was an ashshaker in a coal furnace.If you can tell me anything about it I would really appreciate it Answer: Justin, all coal furnaces have shaker grates because the coal ash will not drop into the ash pan unless you shake it. Hard coal (anthracite) was actually first burned in Eastern Pennsylvania and a number of manufacturers of furnaces and stoves were found here. In addition, the coal was used to melt iron, so foundries (casting facilities) were started to make stoves, farm implements, etc. Coal was the single most important form of energy for the Eastern Pa Economy for a time period of over 100 years. Oil then replaced it in many instances, however coal is still used widely today in the region.