On the 7th of April Mary left for Brussels, after giving an audience to Morosyne, who saw that "she was in the dumps," although she smiled two or three times and tried to hide her feelings.[438] By this time she had probably realized how fruitless all attempts to conciliate the German Princes would prove. The Electors unanimously declined to sanction the agreement which had been the cause of so many heart-burnings, and it remained a dead letter. The Archbishop of Treves declared that there could only be one Emperor in Germany and one sun in heaven. The Palatine, says Morosyne, like the wise old fox that he was, replied that so important a question needed time for consideration, and Joachim of Brandenburg vowed that he would never consent to a scheme which would be odious to all Germany.[439] Philip returned to Spain at the end of May, and the Emperor was reluctantly compelled to accept the inevitable, and surrender the long-cherished hope that his son would succeed to his vast empire. VI. While the eyes of all Europe were fixed on the imperial family at Augsburg, Christina waited anxiously for news in her palace at Nancy. She had sent two of her Italian secretaries, Innocenzo Gadio and Massimo del Pero, to wait on the Queen of Hungary, with strict orders to keep her informed of all that was happening. Gadio's cipher letters have unluckily disappeared, but some of those addressed to him by Niccolò Belloni have recently been discovered in a private library near Pavia.[440] Belloni belonged to a good Milanese family, and had, at his parents' entreaty, been retained by the Duchess in her service when she left Italy. He had succeeded Benedetto da Corte as master of her household, and followed Christina to Lorraine. Niccolò enjoyed his mistress's complete confidence, and his letters to Messer Innocenzo reveal all that was passing in her mind at this critical moment. On the 2nd of January, 1551, he writes: "HONOURED FRIEND,