The collection contains an array of documents and drawings devoted, on the whole, to the two main focuses in Will's life, namely the Colony at Aurora and his thirty years with the Salem Water Department. The correspondence forms a separate series and is arranged chronologically from 1877 to 1981. It consists largely of letters from Frederick Skiff, an Americana specialist who shared an interest in Aurora.

The bulk of the collection consists of material relating to the settlement at Aurora, including articles, manuscript and printed, written by Will; voluminous, though at times repetitive, notes on the history of Aurora; a scrapbook of obituaries and newspaper clippings about the Aurora colonists and their descendants; papers about Aurora by other writers; Clark Will's portraits, drawings, and maps of Aurora's settlers, their homes and their life on the Oregon Trail; and music scores, both handwritten and printed, used by the Aurora band from its inception in Bethel, Missouri, to its demise in 1920.

Will's articles in their final, or near-final, form have been grouped together while the assorted notes have been arranged in a rough chronological order that takes the Aurora settlers from Germany to Oregon by way of Bethel, Missouri and the Oregon Trail. While there are some primary resources in the collection, Mr. Will mostly collated the work of others in his study of Aurora. As a result, a wealth of secondary information is provided on the history of Aurora, pioneer life in the Pacific Northwest, and the joys and tensions of communal living. Of special interest to historians of the Oregon Trail is the information on the Aurora Colonists' trek across the United States. With the preserved body (literally pickled in alcohol) of Dr. Keil's son, Willie, at the van of their wagon train, hymns constantly on their lips and a habit of sharing their meals with Indians they encountered, the settlers of Aurora crossed the American continent unscathed at a time when a goodly percentage of their fellow migrants were being attacked by the native tribes. It appears that the Indians, who were in awe of the corpse, intrigued by the singing, and won over by the food, made a point of distinguishing between Germans (and French Canadians) whom they tolerated and Americans whom they cordially detested.

A second interest of Will's is reflected in the manuscripts and research materials relating to the history of Salem's water supply, including several maps and drawings of Salem's aquatic arteries and the machinery that services them.

One box of negatives, prints, and slides, which have been removed to the Photograph Collection, are mostly concerned with the architecture of Aurora, though some slides of Salem's waterworks are also included. Of note are a glass plate photograph of Dr. Keil and a picture of the Aurora Colony band. A World War II United Way broadside has been removed to the Broadside Collection.