19 Tons of Soot Fall Annually on City Block
From The Indianapolis Star, Friday, November 21, 1919: Nineteen tons of soot is falling annually for each city block in the downtown Indianapolis area. This conclusion was arrived from calculations made by students in the night school physics class at Manual Training High School who conducted tests under the direction of their teacher Louis Karns. Using equipment similar to rain gauges that were placed on the rooftops of downtown buildings, the average sootfall collected a