 Less than a month later, Union troops arrested Alexander Boteler at his home, "Fountain Rock" outside Shepardstown and imprisoned across the river.He convinced his captors to release him, but Union troops burned his cement mill on August 19, 1861, as an alleged snipers nest.The "Pleasant Valley" area was often contested; various troops would burn his plantation's fields many times during the conflict, and Union forces would captured four Confederate cannon in the mill ruins following the Battle of Antietam.