Original sentence: Although the unit as it existed at the time was present at the  Battle of Hatcher's Run near Dabney's Mills on February 5-7, 1865, the 40th New Jersey participated in their first and last battle on April 2nd at Petersburg, where it participated in the final Union army assaults on Confederate entrenchments
Edited sentence: Although the unit as it existed at the time was present at the Battle of Hatcher's Run near Dabney's Mills on February 5-7, 1865, the 40th New Jersey participated in their first and last battle on April 2nd at Petersburg, where it participated in the final Union army assaults on Confederate entrenchments