Rubuta ci gaba don wannan sakin layi - Mutum ya shiga aikin sa kai a cikin rukunin sojojin New York na 98 na Union Army a 1861 a lokacin yakin basasar Amurka kuma ya zama babban. Ya shiga cikin yakin Yorktown, Williamsburg, da Fair Oaks
Ka yi haƙuri. Lafiyarsa ta lalace saboda bayyanar da abubuwa a lokacin yakin kuma an tilasta masa yin murabus daga soja. Daga nan sai ya koma gidansa a Franklin County, inda ya ci gaba da zama lauyan gundumar. A shekara ta 1863, Man ya tafi Washington a matsayin shugaban Sashen Kungiyar a ofishin Mai Kula da Kudin, bayan haka ya yi aiki a karkashin Hugh McCulloch na Ma'aikatar Baitulmalin Amurka. A shekara ta 1866 ya zama mai ba da kuɗi da kuma babban manajan kamfanin National Bank Note Company na Birnin New York. Da yake ci gaba da aikin doka a shekara ta 1871, ya zama babban manajan kuma wakilin Lorillard Estates na Birnin New York kuma ya kasance a wannan matsayi har zuwa 1883.