Subjects Filtration

Black-and-white image of a table with numbers in columns

Bacteria in Delaware River, Torresdale Filters, 1913

Belmont Filters construction 1903

Belmont Filters construction, 1903

Finished Upper Roxborough filters, 1903

Finished Upper Roxborough filters, 1903

Upper Roxborough filter beds

Upper Roxborough filter beds under construction, July 1902

A.C. Abbott, MD

A.C. Abbott, MD

McDonnell filter advertisement

McConnell Germ-Proof Filters ad

Two bottles of water from a river, one dark with pollution and one clear after filtration

Water Before and After Roxborough

Black-and-white photograph showing the completed Upper Roxborough Filter system. Vaulted concrete ceiling with beds of filter sand.

Upper Roxborough Filter Beds Complete, 1903