 Complete the following phrase:  During the Marian Civil War the castle was held by William Kirkcaldy of Grange for Mary, Queen of Scots. He modified and strengthened the spur. Workers were reinforcing the spur in April 1571 with earth in baskets called gabions when a man fell to his death. The spur was described by Rowland Johnson, Surveyor of Berwick who came to assist the siege of Edinburgh Castle on 26 January 1573 during 