Actor Arch Ellwein portrays Sgt. John Ordway of the Lewis and Clark Expedition Monday night at 7:00 p.m. at the Cultural Heritage Center in Pierre.  Ellwein, who also portrays colorful historical figures like President Theodore Roosevelt, steamboat captain Grant Marsh and buffalo hunter Yellowstone Vic Smith, talked about John Ordway whose well-written, vivid descriptions provided important details about the 1804-1806 expedition.