Her life-story is a marvellous instance of genius devoted to the attainment of a high position. The daughter of a well-to-do squire, she was married at fifteen to a wealthy young gentleman whose estate lay ten miles away, and who, dying very soon, left her mistress of the greater part of his fortune. Her first house at Barlow, near Chesterfield, has entirely disappeared, save for a piece of old wall. She remained a widow for many years, then married Sir William Cavendish, by whom she had six children. After his death she chose Sir William St. Loe, inherited his extensive estates, then, well past her prime, accepted the offer of the widowed George, Earl of Shrewsbury; but before the marriage insisted that two of her young Cavendishes should be married to two of his young Talbots. For a few years her fourth venture proved satisfactory enough; but the custody of Mary Queen of Scots apparently became too much of a nerve-strain for both man and wife; and their wrangles finally became common property in high circles. She embroiled herself with Queen Elizabeth; she persecuted her husband for his so-called meanness--although she was exceedingly rich in her own right; and, worst of all, she sowed dissension between him and his own offspring. The poor earl's condition was melancholy enough; one has no doubt that he was thankful to the heart when they separated for the last time. In the portrait at Hardwick Hall she is represented as a comely, roguish-looking matron in full maturity: a better idea of her character may be won from the effigy lying on the tomb she erected for herself in All Saints' Church at Derby. There one sees a face not unbeautiful, but cold and masterful in the extreme. It was her grandson, William, first Duke of Newcastle, who first gave lustre to Welbeck, and perhaps, after all, he owed most of his celebrity to an intellectual wife, known in Restoration days as "Mad Madge of Newcastle". Few pictures of domestic life in the seventeenth century are more pleasing than that given by this lady in the short account of her girlhood, which opens her fantastical autobiography. Born the youngest of Sir Thomas Lucas's eight children, in a large country house near Colchester, she was trained under a system of education originated by her mother. The daughters, of whom there were five, were not kept strictly to their schoolbooks, but rather taught "for formality than benefit". Singing, dancing, music, reading, writing, and embroidery were their accomplishments; but Mistress Lucas, who was left a widow soon after the birth of Margaret, cared not so much for dancing and fiddling and conversing in foreign languages as that they should be bred modestly and on honest principles. In London, where they migrated for the season, they would visit Spring Gardens, Hyde Park, and similar places, and sometimes attended concerts, or supped in barges on the river.