"Volun'eer (sic) Sappers and Miners from the F.F.V or Merchandise Contraband of War." Caption: "Massa Butler, we's jest seceded from Harpers Ferry, whar we larn'd de trade ob making Trenches and Forti'cations. And now if yer wants anything done in dat ar line ob bisness, we's de Niggers to call upon. We borrow'd des yer tools at de Ferry, and if dey is'ent Contraban we's gwine to carry em back at de close ab horsetilities." Contrabands (slaves) talking to Union General Benjamin Butler