This collection contains the American Civil War diary of Corporal John R. Maybury of Company L, 10th New York Cavalry. The first entry in the diary (January 1, 1864) finds Maybury encamped in northern Virginia and describing routines of camp life (drilling, washing clothes, policing quarters, buying goods from the sutler, picket and forage duty, drawing a new uniform, inspection, building quarters). The weather conditions are noted on a daily basis.

In March, contacts with civilians and enemy combatants grow more frequent, with references to taking prisoners (soldiers, a lady spy and bushwackers) and denying passage through the lines. Maybury makes occasional reference to camp rumors, such as a supposed sighting of Stuart's cavalry and the taking of Richmond by Kirkpatrick. In May, the regiment sees more action, with Maybury noting the capture and burning of Virginia Central Railroad supply trains at Beaver Dam Station, the capture of guns at Ashland, heavy fighting near Richmond, and a description of action at the Battle of Haw's Shop. For the next several months, Maybury alludes to frequent skirmishes and battles with the Confederates. In the fall, Maybury's entries revert to camp activities and routines (including mention of an inspection by generals Meade and Gregg), with less frequent references to engagements with the enemy. The diary ends with Maybury traveling to the hospital, following the wound he had sustained the previous day. At the end of the diary are a few notes made by Maybury on the clothing he had drawn in service and the pension had had drawn afterward.

The collection also contains a metal stencil bearing Maybury's name and unit and a small piece of cloth on to which Maybury's name has been stenciled.