Item Types Image

Diagram showing the Philadelphia Water Department's water treatment process

PWD Drinking Water Treatment diagram

Diagram and description of the typhoid bacteria

Typhoid bacteria diagram, 1905

Black-and-white image showing several cubic measurements of various types

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

Black-and-white line graph showing two jagged lines on a grid

Diagram Showing Decreased Amount of Dissolved Oxygen in Delaware River, 1913

Drawing in blue ink on beige paper depicting reservoir, dam and standpipe heights

Diagram showing heights of reservoirs, dams, standpipes &c, 1894