 Complete the following phrase:  Throughout the 18th century the unused, neglected fortifications deteriorated and were not properly repaired until the 1801 coronation of Alexander I. In one season the moat with bridges and adjacent buildings was replaced with a clean span of paved square. More reconstruction followed in the 19th century. The stretch of Kremlin wall south from Senate Tower was badly damaged in 1812 by the explosion at the Kremlin Arsenal set off by the 