Letter from Malvina C. Thompson (secretary to First Lady Eleanor Roosevelt) to Edwin M. Ross instructing him that the samples of water fabricated by Betz Laboratories to duplicate London City water has arrived. Mrs.…

Letter from First Lady Eleanor Roosevelt to Edwin M. Ross in which Roosevelt accepts Ross's offer to analyze and duplicate London city water which would be used to serve tea to the King and Queen of England.

General view of an unidentified employee preparing a water sample for testing at a Dearborn Chemical Company's laboratory facility in Chicago, Illinois. A stamp on the verso of the photograph for "The Fensholt Company,"…

Print advertisement for ethylene dibromide manufactured and sold by the Dow Chemical Company for use in Ethyl gasoline. The advertisement features a seascape and an illustration of a mermaid, with accompanying text…

General view of Dearborn Chemical Company representative C.M. Kesler (seated) and hospital employee "Mike" examining a sample of water at Mary's Help Hospital (now Seton Medical Center) in San Francisco, California. Per…

General view of assorted water samples sent to the Dearborn Chemical Company's 35th Street Laboratory for analysis. Founded in 1887, the Dearborn Chemical Company was a corporate ancestor of BetzDearborn, Incorporated…

General view of employee Al Slisg conducting a water analysis test at the Dearborn Chemical Company's 35th Street laboratory and manufacturing facility located in Chicago, Illinois. Founded in 1887, the Dearborn…

General view of employee Ted Slisz using a balance at the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant. Founded in 1887, the Dearborn Chemical Company was a corporate ancestor of…

General view of a storage tank in use at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. The employee visible in the photograph is unidentified. Founded in 1887, the Dearborn…

General view of several employees conducting water analysis tests at the Dearborn Chemical Company's 35th Street laboratory and manufacturing facility located in Chicago, Illinois. The three employees visible in the…

General view of an unidentified employee analyzing unidentified substances at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. A row of Bunsen burners are visible on the work…

General view of employee Anton H.R. Noreen at work at the Dearborn Chemical Company's 35th Street laboratory and manufacturing facility, with view of the laboratory work bench, assorted glassware, and scientific…

Close-up view of scientific apparatus used at the Dearborn Chemical Company 35th Street laboratory facilities located in Chicago, Illinois. Founded in 1887, the Dearborn Chemical Company was a corporate ancestor of…

Close-up view of raw material and machinery used in the manufacture of water treatment chemicals at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887, the Dearborn…

General view of employee Walter Perry filling a barrel with an anti-foam water treatment produced at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887, the Dearborn…

Close-up view of machinery used in the production of water treatment chemicals at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887, the Dearborn Chemical Company…

Close-up view of machinery used in the production of water treatment chemicals at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887, the Dearborn Chemical Company…

General view of employee Joe Korn operating a boiling tank used in the manufacture of liquid water treatments at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887,…

General view of employee James Nelson at work in the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant. An assortment of beakers and laboratory apparatus are visible on the work bench.…

General view of employee Jack Cooney operating a boiling tank used in the manufacture of liquid water treatments at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in…

Close-up view of employee Irin Crocker using a balance at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Founded in 1887, the Dearborn Chemical Company was a corporate ancestor…

General view of employees (left to right) Ray Shoan, Charles S. White, Andrew Lombardi, and Bernard Tarley conducting water analysis tests at the Dearborn Chemical Company's 35th Street laboratory and manufacturing…

General view of several employees at work in the Dearborn Chemical Company's 35th Street laboratory and manufacturing facility located in Chicago, Illinois. The three employees visible in the foreground are identified…

General view of employee E.L. Konigsmark recording water samples sent to the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant for analysis. Founded in 1887, the Dearborn Chemical…