...hundred engineers; thirty-six pieces of field artillery, thirty Parrott guns, twenty-seven siege and three Cohorn mortars, besides ample tools and material. Admiral Dahlgren was to co-operate. On Folly Island , in our possession, batteries were constructed near Lighthouse Inlet, opposite Morris Island, concealed by the sand hillocks and undergrowth. Gillmore's real attack was to be made from this point b...