On July 3, 1997, at 1745 central daylight time, a Snow S2C, N1684S, operated by a commercial pilot, collided with the terrain during a forced landing following a loss of engine power. The accident occurred in Viola, Illinois. The pilot was not injured and the airplane was substantially damaged. The 14 CFR Part 137 aerial application flight was operating in visual meteorological conditions without a flight plan. The flight originated from the Aledo, Illinois, at 1458 cdt. The pilot reported he had a full chemical load and a full load of fuel (100 gallons) on takeoff. He reported he sprayed 6 different fields and while spraying the last field a loss of power occurred. The pilot attempted to circle around and land in the field which he was spraying. The airplane touched down in the field; however, it continued to travel across a road and an embankment prior to coming to rest. Inspection of the airplane immediately following the accident revealed a lack of fuel in the fuel tanks. See attached Illinois State Police Aircraft Accident Report. In addition, the owner/operator of the airplane stated the pilot ran the airplane out of fuel.