The Civil War Soldiers and Sailors Database ( http://www.itd.nps.gov/cwss/ ) shows two Confederate soldiers by the name of Thomas Bullock:

Thomas J. Bullock, a private, served with the 6th Alabama Infantry.
Thomas S. Bullock, a corporal, served with the 21st Alabama Infantry.

There are no Union soldiers appearing in this database under the name Tom, or Thomas, Bullock.

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