The monument to the 1st United States Artillery, Battery H is south of Gettysburg in the National Cemetery. (39.819628° N, 77.230918° W; Google map; Tour map: National Cemetery)

Monument to the 1st United States Light Artillery, Battery H at Gettysburg

From the monument:

Army of the Potomac
Artillery Reserve
First Regular Brigade 

Battery H First U. S. Artillery 

Six 12 Pounders
Lieut. Chandler R. Eakin Commanding

July 2. In position on Cemetery Hill facing the Emmitsburg Road. Engaged July 2nd and 3rd. Lieut. Eakin severely wounded after his guns went into battery and the command devolved on Lieut. Philip D. Mason.

Casualties Killed 1 Man Wounded 1 Officer and 7 Men Missing 1 Man

See more on Battery H, 1st United States Artillery in the Civil War