Mr. Wentorf was both a local photographer and a collector of historical photographs. The images focus on local landmarks, industries, institutions, special events and people going about daily life in Two Rivers. Many of the photographs include group shots of organizations and civic groups.

On July 21, 1891, the Manitowoc County Chronicle reported, “Work on the library building is now in progress” and on October 13, “The building for the Joseph Mann Library is nearly completed.” The two-story front-gabled frame library building was located on Lots 3 and 4, Block 72, south of Main (now Sixteenth) Street between Washington and Adams Streets. The total cost of construction, heater, furniture and books was $3,363.73.