


Volume of Sludge from 1,000,000 Gallons of Sewage

Diagram Showing Rate Between Bulk of Wet Sludge and Its Percentage Moisture

Sludge Drying Beds, Essen Nord, Germany

Effects of Expansion of Gas Bubbles in Enscher Sludge Shown in Right-Hand Cylinder

Thomas Run sewer outlet during construction

Bacteria in Delaware River, Torresdale Filters, 1913

Pipe Test, 1914

Swimmers at Pier 126, Delaware River, July 15, 1918

Allegheny Avenue Sewer at Pier 126, 1918
