Collections : [University of Michigan Bentley Historical Library]

The Correspondence series (1918-1991, approximately 3 linear feet) consists of letters written to and from the multiple members of the extended Lewis family. Parents Ralph and Roberta are the largest contributors to this series, often signing off their letters to their children as "MODAD" (likely to stand for a combination of "Mom" and "Dad"). Early letters from Reberta to her immediate family are often signed with either "Berta" or "Bertie". The letters offer insight into the day-to-day life of the individual who wrote them during their travels abroad, and span from 1918 to 1991, four generations of the Lewis family, and topics ranging from birth certificates to funding.

The Correspondence series (1893-1947) is divided into three subseries: General, Personal, and Miscellaneous. General Correspondence concerns a variety of topics, mainly medical, including discussions of writings, studies, lectures, and clarifications of laboratory procedures. Personal Correspondence contains correspondence reflecting personal and family concerns. Of particular interest are two letters written by Warthin to "Dear Friend" from Vienna in the summers of 1893 and 1894 in which he shares his reactions to life in Vienna and the medical processes of the time. Also included is a folder of correspondence from Sir William Osler, who in many ways was Warthin's mentor. Miscellaneous Correspondence contains correspondence received by Warthin and Dr. Carl Vernon Weller. Weller served on the staff with Warthin and succeeded him as chairman of the Department of Pathology. Some of the correspondence addressed to Weller is written after Warthin's death which accounts for the collection's later dates.

The Correspondence series (0.7 linear feet) is arranged chronologically and spans the years 2004 to 2012. The early correspondence documents initial conversation between Dow Chemical Company, government officials, and other local environmental organizations discussing the chemicals founding within the Saginaw and Tittabawassee River as well as early efforts to clean the river. Later correspondence, from 2007 and beyond, covers the requests made by the city of Midland and members of the Lone Tree Council for reports and statistics of the actions taken by Dow Chemical Company. Some of the correspondence comes directly from Michelle Hurd Riddick, an active member of the Lone Tree Council during the mid to late 2000s.