As years passed by and Elizabeth remained unmarried and averse to the mention even of a successor, the question became acute, not in England only but throughout Europe. Spain and France were anxious to have a Catholic sovereign in England; but neither wanted the other to have the added strength of England as a dependency. Elizabeth kept playing them off one against the other with her various matrimonial schemes; and Mary was in correspondence with them, trying to exact promises of assistance. Intrigue grew more and more involved. At last matters came to a head. It became recognized, after the dismissal of the Duc d'Anjou as a suitor, that Time itself would no longer permit a marriage for Elizabeth. The Catholics in larger numbers resolved that her death was imperative and the death of her strong supporters. Elizabeth with the fearlessness of true strength had allowed Mary great freedom of correspondence in her confinement. Now she cut her off from the outside world, until a diplomatic necessity arose to know exactly how far foreign powers were prepared to support Mary, how far they were speaking their true intentions in their dealings with Elizabeth. Walsingham had spies in every influential Catholic household in England, at all the Courts and even the Jesuitical centres in Spain and France. But the information was not yet sufficient. Nothing illustrates more effectively the extraordinary difficulty of obtaining accurate news in those days of slow travelling and messengers, than the elaborate method which Walsingham and Elizabeth were obliged to arrange at this juncture. It is a mistake to suppose it illustrates the treachery and deceitfulness of the times. The times have changed not in moral tone but in quickness of transit. Men are very much the same; but steam and electricity, the telegraph, the telephone, and a postal system have altered the aspect of affairs and the methods of conducting business or intrigue.