James Mease kept his journal during two separate periods: during a trip through eastern Pennsylvania and New York state, August-September 1835 (pp. 1-62), and during a journey to Washington, D.C., in the summer of 1841 (pp. 63-75). Laid into the volume is a half-sheet containing a partial letter by Mease to one of his sons and some travel notes.
Although the journal is not signed, it has been attributed to Mease because of direct references it makes (pp. 16, 71) to his essay "Description of Some of the Medals Struck..." The handwriting was subsequently shown to match other Mease manuscripts in the Clements Library. Mease's On Utility of Public Loan Offices and Savings Funds by City Authorities (1836) is of interest in that the journeys recorded in the first part of the Clements Library's journal appear to have been taken to gather information for that work.
Two themes run throughout Mease's journal. The first is his strong sense of history. Mease was careful to note historical events which had occurred on sites he was visiting -- making reference both to events which he had witnessed and about which he had read. The second theme is his interest in people, particularly the "common man." Mease enjoyed the friendship and society of some of the most noted persons of his day, yet he was fascinated by a visit with an ordinary citizen, exploring that person's life story, which he would record in his journal.