Topics Technology & Engineering

Black-and-white photograph of a man in a hat standing in a brick trench

Grit Chamber, Essen, Germany

Black-and-white photo of heavy machinery

Sludge Presses for Grease Recovery, Bradford, England

Black-and-white image of a tray with three compartments and four small glass cylinders

Drain water from sludges obtained from sedimentation, septic and Emscher tanks

Spring Garden Sewage Experiment Station, used to test water filtration methods

Outside Sprinkling Filters, Spring Garden Sewage Experiment Station, 1911