Bulgarian archaeologists stumbled upon unexpected treasure this week during a dig in an ancient Roman sewer - a well-preserved, marble statue depicting the Greek god Hermes.The discovery of the 6.8-foot (2-metre) tall statue was made during excavation work at the site of the ancient city of Heraclea Sintica in southwestern Bulgaria, which lies close to the Greek border.Archaeologists leading the work said that after an earthquake devastated the sprawling city in about A.D. 388, the statue had been carefully placed in the sewers and covered with soil, explaining its good condition."Its head is preserved. (It's in a) very good condition....