Salisbury, despairing of being able to take the place, either by treachery or by storm, turned the siege into a blockade, closely investing the castle by sea and land, and tried to starve the garrison out into a surrender. Alexander Ramsay, hearing of the extremities to which Black Agnes was reduced, embarked with a party of forty resolute men, eluded the vigilance of the English, and entered the castle, under cover of night, by a postern next the sea. Sallying out again, they attacked and dispersed the advanced guard of the besiegers. Salisbury, disheartened by so many reverses, withdrew his forces, after having remained before Dunbar for nineteen weeks. About this time the duchy of Brittany was the subject of contention between two rivals, John, Count de Montfort, son of the late duke, and Charles of Blois, who had married the duke's granddaughter. Philip de Valois, King of France, decided the dispute in favour of Charles, and despatched a large army to establish him in the capital. Edward III., of England, at once declared for the Count de Montfort, as an enemy to the house of Valois, which he--King Edward--wished to drive from the throne of France. The count was betrayed into the hands of his rival by some malcontent nobles. But Jane, the brave countess, sustained his sinking fortunes "with the courage of a man and the heart of a lion." Directly the news of her husband's capture arrived at Rennes, where she resided, the countess assembled the citizens, showed them her infant son, and entreated them not to desert the last male heir of their ancient dukes. Her eloquence, beauty, and courage produced a magical effect. The people swore to defend her and her son to the last extremity. The countess next visited all the strongholds throughout Brittany, and excited the people to resist the French, and to adopt the requisite measures of defence. Then, sending her boy to England, she shut herself up in Hennebonne, and there awaited the reinforcements promised by King Edward. Charles of Blois entered Brittany, captured Rennes, and despatched a force, commanded by Prince Louis of Spain, to besiege Hennebonne. The garrison, animated by the presence of the valiant countess, made a resolute defence. Jane herself performed prodigies of valour. Clad in armour from head to foot, she stood foremost in the breach, sustaining every attack of the foe with the utmost _sang froid_, or ran from post to post, according as the troops required encouragement or reinforcement.