Elisha Boles is not listed in the PA Archives ARIAS Card Index or S. P. Bates' "History of the PA Volunteers, 1861-1865;" however, I did find:

Elijah Boles
Private
Company G
6th PA Artillery/212th Regiment P. V.
August 24, 1864
Mustered out with Battery, June 13, 1865

You can read the history of the 6th PA Artillery and the muster rolls on my PA in the Civil War website at:
http://www.pa-roots.com/~pacw/