This collection contains five letters written among brothers James P., T. K. and Calvin S. Gay, of South Auburn (Susquehanna County), Pennsylvania, while all were serving in the Union Army during the American Civil War. The letters are written from camps in Virginia, Pennsylvania, Tennessee, and Maryland.

In three letters written to his brother Calvin between February and May, 1864, T. K. Gay, serving in the U. S. Signal Corps, recounts his unit's movement from Washington D. C. to Knoxville via Pittsburgh. He describes a cursory inspection in Knoxville and provides a humorous account of a false alarm in camp. He notes that his camp is in the what had been the garden of a wealthy local resident and adds that Union troops had burned down the house, cut down the trees, and destroyed the flower gardens. Gay also mentions Copperheads back home.

In a letter to his brother Charles, James P. Gay, of the 4th Pennsylvania Reserves, provides instructions for having his father bring a wagonload of supplies to Gay in camp in the Fredericksburg, Virginia, area. Gay also provides instructions for the making of a pair of boots that he wants brought to him.

Writing from Cumberland, Maryland, to his brother James, Calvin S. Gay describes his regiment's recent inspection and parade. He also writes of personal matters, telling James to stay away from his girlfriend: "[Y]ou spoke of Hatty & myselfe of being intimate you better bet we are & would like to have you let her alone while I am absent I hear that you have got to Robing folks since I came away & for this reason would like to have you keep hands off from Hatty."