ɡɹˈɛɡ sˈɜːvd ɪn kˈʌmpəni ˈiː, ðə "sˈɛntɚ ɡˈɑːɹdz," ʌvðə fˈɪfθ pˌɛnsɪlvˈeɪniə ɹɪzˈɜːv ɹˈɛdʒɪmənt æz ɐ luːtˈɛnənt.
Gregg served in Company E, the "Centre Guards," of the 5th Pennsylvania Reserve Regiment as a lieutenant.