Diagram from sewage treatment plan for Philadelphia, 1912
Southwest Sewage Treatment Plant under construction, 1949
CITIZENS’ BUSINESS: 1939-1946
Three reports on Philadelphia’s Sewage Treatment Project, 1911-1914
Emscher Tank Installation at Essen Nord, Germany
Effects of Expansion of Gas Bubbles in Enscher Sludge Shown in Right-Hand Cylinder
Drain water from sludges obtained from sedimentation, septic and Emscher tanks