The journal is a stitched pamphlet (19 cm.) of 12 leaves, with 21 pages of entries in Harris's hand. The entries record the progress of a surveying expedition up the North Branch of the Susquehanna River, in present-day Bradford County, Pennsylvania. The journal commences on 14 October 1774, when Harris was below the confluence of Wyalusing Creek and the Susquehanna, and runs through 1 December, and the conclusion of the party's work. Entries appear for most days during that span; the typical entry is between 150 and 200 words. Much of the content consists of Harris's surveyor's field notes, but entries also include descriptions of the party's movements, observations on the land and weather, and one extended account (on 8 November) of a council with an unidentified Indian "King or Chief" concerned with the party's possible encroachment on Native land. The surveys recorded in the journal were made on lands lying along, and to the east of, the Susquehanna, immediately south of the "42 degree" (i.e., the New York line). The Iroquois had sold a sizeable portion of the area to Pennsylvania in 1768, but viewed the region north of the Chemung-Susquehanna confluence as the gateway to the lands of the Iroquois confederation.

The broader context of the expedition is not much alluded to in the manuscript. At the volume's conclusion Harris notes that "[T]he aforgoing Jornel and field notes are the work and Proceedings don for Robt Lettis Hoopper and Comp. by him". Hooper (c1730-1797) was probably the chief surveyor in the party; he had contracted to perform many surveys for Pennsylvania proprietors. Also involved with the expedition was Samuel Wallis (1730-1798), who had arrived in Lycoming County around the same time as Harris, and became known as the "Land King" for his tireless acquisition and speculation.

Accompanying the journal is an undated, unsigned record docketed "List of Proprietary Property of Sundry favourite grants." The relationship between this document and the journal is unclear. A typical entry notes the owner and location of a particular property in very general terms. The locations of the properties run across Pennsylvania from east ("Dr. ... 3000 included on old Indian Town on Delaware [River]) to west ("Alex'r McKee 500 at the mouth of Chartiers Creek 5 mile below Ft. Pitt"). Some areas listed in the document are also mentioned in Harris's journal, such as Lycoming Creek and Loyalsock.