close-carts or wagons for the munitions. He estimated the invasion force would last only four to five days in England before it ran out of provisions. He suggested, from the safety of Berwick-upon-Tweed, that the Scots could be vanquished by a modest English force attacking from north and south in a pincer movement. The Scottish host assembled near Edinburgh and James IV and Warbeck offered prayers at Holyrood Abbey on 14 September, and on the next day at St Triduana's Chapel and Our Lady Kirk of Restalrig. On 19 September 1496 the Scottish army was at Ellem and on 21 September they crossed the Tweed at Coldstream. Miners set to work to demolish Heaton Castle on 24 September, but the army quickly retreated when resources were expended, and hoped-for support for Perkin Warbeck in Northumberland failed to materialise. According to an English record, the Scots penetrated four miles into England with a royal banner displayed, and destroyed three or four little towers (or Bastle houses). They left on 25 September 1496 when an English army commanded by Lord Neville approached from Newcastle. When news of this invasion reached Ludovico Sforza, Duke of Milan, on 21 October 1496, he wrote to his ambassador in Spain, to request the Spanish monarchs make peace between England and Scotland. The peace mission was entrusted to the Spanish ambassador in Scotland, Pedro de Ayala, who had been Perkin's companion in Northumberland.<ref>Calendar State Papers Milan" (London, 1912), no. 514.</ref> Later, wishing to be rid of Warbeck, James IV provided a ship called the Cuckoo and a hired crew under a Breton captain, Guy Foulcart. Horses were hired for 30 of Warbeck's companions to ride to the ship at Ayr on 5 July 1497. Pedro de Ayala accompanied Perkin to Ayr. Perkin pawned a horse for cash in Ayr and sailed to Waterford in shame. James IV made peace with England by signing the Treaty of Ayton at St Dionysius's Church in Ayton in Berwickshire. Once again Perkin attempted to lay siege to Waterford, but this time his effort lasted only eleven days before he was forced to flee Ireland, chased by four English ships. According to some sources, by this time he was left with only 120 men on two ships. Bacon's History of the Reign of King Henry VII said he had "in his company four small barks, with some sixscore or sevenscore fighting men".