But since then, men had "digged villainous saltpeter out of the bowels of the harmless earth" to manufacture powder, and others had invented cannon (S239), "those devilish iron engines," as the poet Spenser called them, "ordained to kill." Without artillery, the old feudal army, with its bows, swords, and battle-axes, could do little against a king like Henry, who had it. For this reason the whole kingdom lay at his mercy; and though the nobles and the rich might groan, they saw that it was useless to fight. 332. The Pretenders Symnel and Warbeck. During Henry's reign, two pretenders laid claim to the crown: Lambert Symnel, who represented himself to be Edward Plantagenet, nephew of the late King; and Perkin Warbeck, who asserted that he was Richard, Duke of York (S310), who had been murdered in the Tower by his uncle, Richard III. Symnel's attempt was easily suppressed, and he commuted his claim to the crown for the position of scullion in the King's kitchen. Warbeck kept the kingdom in a turmoil for more than five years, during which time one hundred and fifty of his adherents were executed, and their bodies exposed on gibbets along the south coast of England to deter their master's French supporters from landing. At length Warbeck was captured, imprisoned, and finall hanged at Tyburn. 333. Henry's Politic Marriages. Henry accomplished more by the marriages of his children and by diplomacy than other monarchs had by their wars. He gave his daughter Margaret to King James IV of Scotland, and thus prepared the way for the union of the two kingdoms in 1603. He married his eldest son, Prince Arthur, to Catharine of Aragon, daughter of the King of Spain, by which he secured a very large marriage portion for the Prince, and, what was of equal importance, the alliance of Spain against France. Arthur died soon afterward, and the King got a dispensation from the Pope, granting him permission to marry his younger son Henry to Arthur's widow. It was this Prince who eventually became King of England, with the title of Henry VIII, and we shall hereafter see that this marriage was destined by its results to change the whole course of the country's history. 334. The World as known at Henry's Accession (1485). The King also took some small part in certain other events, which seemed to him, at the time, of less consequence than these matrimonial alliances. But history has regarded them in a different light from that in which the cunning and cautious monarch considered them.