General view of Dearborn Chemical Company employee E.P. Fager comparing the color of two solutions during a water sample field test. Assorted glassware and a Dearborn portable testing cabinet are visible on the table.…

General view of the main room at the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois, with view of assorted glassware and scientific…

General view of a section of the main room at the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois, with view of assorted glassware and…

General view of a section of the main room at the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois, with view of assorted glassware and…

General view of a section of the main room at the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois, with view of assorted glassware and…

General view of the drug storage room at the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois. Founded in 1887, the Dearborn Chemical…

General view of a portion of the Dearborn Drug and Chemical Works (later Dearborn Chemical Company) 35th Street laboratory facilities located in Chicago, Illinois, with view of furnaces, assorted balances, and…

Elevated view of employees Charles S. White (left) and Andrew Lombardi (right) at work in the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Per notations accompanying the…

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 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 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…

General view of employee Ted Slisz at work in the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant. An assortment of beakers is visible on the work bench. Founded in 1887, the Dearborn…

General view of employee Charles S. White analyzing unidentified substances at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Assorted scientific apparatus and laboratory…

General view of employee Anton H.R. Noreen preparing samples for testing 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 Anton H.R. Noreen conducting an analysis of coal samples at the Dearborn Chemical Company's 35th Street laboratory and manufacturing facility located in Chicago, Illinois. Founded in 1887, the…

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…

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 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 at work in the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant. A variety of titration equipment and other scientific apparatus are visible on…

General view of employee Al Herman analyzing an unidentified substance at the Dearborn Chemical Company's 35th Street laboratory facility and manufacturing plant. Assorted scientific apparatus and laboratory glassware…

General view of employee Genevieve Work in the Receiving Room at the Dearborn Chemical Company's 35th Street Laboratory facility and manufacturing plant. Per notations accompanying the photograph, the Receiving Room was…

General view of Dearborn Chemical Company employee C.B. Smith utilizing a concentration hydrometer during a water sample field test. Assorted glassware and a Dearborn portable testing cabinet are also visible on the…

General view of two unidentified men utilizing a Dearborn Chemical Company portable testing cabinet to conduct a water sample field test. Founded in 1887, the Dearborn Chemical Company was a corporate ancestor of…

General view of Dearborn Chemical Company engineer F.B. Horstmann utilizing a portable testing cabinet to conduct a water sample field test. A stamp on the verso of the photograph for "The Fensholt Company," a public…