In the Middle Ages, chemistry and mathematics were things known to few people except the monks; any man who studied the sciences was styled an alchemist, and suspected of being in league with the Evil One. When it was a woman who gave herself up to learned studies, the people could scarcely be withheld from tearing "the sorceress" to pieces. Occasionally, however, despite what the world said, noble ladies, especially on the Continent, did apply their minds to what in those days went by the name of the Black Art. Amongst these was Richilda, Countess of Hainault, who married Baldwin the Good, eldest son of Baldwin, Marquis of Flanders, one of whose daughters, Matilda, became the wife of William the Conqueror, and another of Tosti Godwinsson, son of the powerful Earl Godwin. The fame of Richilda as a wicked sorceress caused her to be anything but a favourite in the country; and when her husband died, Robert le Frison, Count of Friesland, and brother of the deceased, endeavoured to wrest Flanders from her young son Arnulf, or Arnoul, who was little more than a boy. William the Conqueror espoused the cause of Richilda, and sent over Fitz-Osbern, Earl of Hereford, the tyrant of the Welsh, to her aid. The Countess also implored the assistance of her liege lord, the king of France. A battle took place on St. Peter's Day, 1071, at Bavinchorum, near Cassel; Richilda and Fitz-Osbern commanded their troops in person. The left wing of the foe was routed, and Robert le Frison made prisoner and sent to St. Omer. But this success was counterbalanced by the death of Fitz-Osbern and young Arnoul. Richilda's forces fled in confusion, and the heroine was made prisoner. An exchange was effected, by which Richilda and the Frison regained their liberty. The countess immediately set about raising fresh troops to avenge the death of her boy. The contending armies met again; this time at Broqueroi, near Mons, where the troops of Richilda were routed with so terrible a slaughter that the scene of the conflict was afterwards known under the name of "the Hedges of Death." All hope now fled the breast of Richilda. Escaping from the field, she took refuge in a convent, where the rest of her days were passed under the severest penances--to atone, as folks said, for her past dealings with the Prince of Darkness. [Illustration] [Illustration] VI. The Crusades--French, German, and Genoese Amazons--Eleonora of Aquitaine--Matilda of Boulogne--Empress Maud--Aldrude, Countess of Bertinoro--Empress Constantia--Nichola de Camville (Barons' Wars)--Blanche of Castille, Queen-Regent of France--Women of Culm--Blanche de Rossi--Black Agnes, Countess of March--Countess de Montfort--Julia du Guesclin--Jane de Belleville, Lady of Clisson--Marzia--Margaret, Queen of Denmark, Norway, and Sweden, the Semiramis of the North--Fair Maiden Lilliard (Chevy Chase)--Lady Pelham--Philippa, Queen of Denmark.