Economics Laboratory employees, 1935.

The Endicott Building, ca. 1900. The first location of Economics Laboratory (later Ecolab) was in the basement of the Endicott Building on Fourth Street in downtown St. Paul.

M. J. Osborn, ca. 1950s. Osborn never finished high school, but the salesman-turned-entrepreneur saw a need for institutional and consumer cleaning products, leading to the 1923 foundation of Economics Laboratory, later known as Ecolab. From Ecolab Company Records, Minnesota Historical Society.

Employees of the research and development division of the Economics Laboratory (later Ecolab) at work on the sixth floor of the Globe Building in St. Paul, 1938. Pictured are John Effinger, Roy Frommer, Clarence Olson, and John Lewis Wilson.

Four small beads from 2009 excavation and one larger bead from 2010 excavations by Dr. Katherine Hayes. Photograph by Don Hoffman.

Photograph of artifacts metal detected by a relic collector prior to 1972 and identified as an iron ferule, a piece of fire steel, a rosehead nail, a fragment from the bottom of a kettle, and an axe head. Printed in Birk, Douglas A., "A Preliminary Study of the Little Round Hill Site, Old Wadena Park, Wadena County, Minnesota." Institute for Minnesota Archaeology, Reports of Investigation, no. 214, 1992, fig. 3.

Sketch of Little Round Hill site with excavation units and shovel test plots indicated. Printed in Katherine Hayes’ “Results of Survey and Excavation of the Little Round Hill (2WD16) and Cadotte Post (21WD17) Sites in Wadena County, Minnesota: A View of the Fur Trade in the Late Eighteenth Century,” a report prepared for the Wadena County Historical Society, 2014.

The Little Round Hill site, surface features, and IMA 1992 excavations. Printed in Douglas A. Birk’s “A Preliminary Study of the Little Round Hill Site, Old Wadena Park, Wadena County, Minnesota. Institute for Minnesota Archaeology.”