From the first moment on which she entered the service of the Queen of Spain, it became her desire to govern not only the queen but the king, and by this means the realm itself. Such a grand project had need of support from our king [Louis XIV.], who, at the commencement, ruled the court of Spain as much as his own court, with entire influence over all other matters. The young Queen of Spain had been not less carefully educated than her sister, the Duchesse de Bourgogne. She had even, when so young, much intelligence and firmness, without being incapable of restraint. Indeed, she became a divinity among the Spaniards, and, to their affection for her, Philip V. was more than once indebted for his crown. Madame des Ursins soon managed to obtain the entire confidence of this queen, and, during the absence of Philip V. in Italy, assisted her in the administration of all public offices. She even accompanied her to the junta, it not being thought proper that the queen should be alone amidst such an assemblage of men. In this way she became acquainted with everything that was passing, and knew all the affairs of the government. This step gained, it will be imagined that the Princess des Ursins did not forget to pay her court most assiduously to our king and Madame de Maintenon. Little by little she introduced into her letters details respecting public affairs, without, however, conveying a suspicion of her own ambition. She next began to flatter Madame de Maintenon, and to hint that she might rule over Spain even more firmly than she ruled over France, if she would entrust her commands to Madame des Ursins. Madame de Maintenon was enchanted by the siren, and embraced the proposition with avidity. It was next necessary to draw the King of Spain into the same net--not a very arduous task. Soon the junta became a mere show. Everything was brought before the king in private, and he gave no decision until the queen and Madame des Ursins passed theirs. [This rule Madame des Ursins continued for many years. Ultimately, a quarrel with Madame de Maintenon, the death of the Queen of Spain, and the second marriage of the king, with the cabals of enemies, forced her in her old age into a retreat at Rome.] She was not long there before she attached herself to the King and Queen of England (the Pretender and his wife), and soon governed them openly. What a poor resource! But it was courtly, and had a flavour of occupation for a woman who could not exist without movement. She finished her life there, remarkably healthy in mind and body, and in a prodigious opulence, which was not without its use in that deplorable court. She had the pleasure of seeing Madame de Maintenon forgotten and annihilated at St Cyr, of surviving her, of seeing at Rome her two enemies, Guidice and Alberoni, as profoundly disgraced as she. Her death, which a few years before would have resounded through all Europe, made not the least sensation. LADY GRIZEL JERVISWOODE. [1665.]