To his other offices he added those of Grand Master of the Ordnance, and Surveyor-General of Public Works. The artillery had always been a favourite branch of the service with him; and he was esteemed one of the best generals of the age for the attack or defence of fortified places. As Master of the Ordnance he mainly contributed to the success of the war with the Duke of Savoy. The army was well paid and provided, the artillery always at its place at the proper time, and a general reform was felt throughout the service. In peace he was not less active in superintending the construction and repair of fortifications; and in those still more valuable labours which tend to facilitate intercourse, and provide for the internal wants of a nation. One of his chief works was a canal to join the Seine and Loire. There were few good engineers in those times, and Rosny, with his usual industry and earnestness, went himself to the spot and superintended the commencement of the work he had projected. In 1606, after many brief quarrels between him and his master, caused chiefly by the intrigues of Henry’s mistresses and worthless courtiers, Rosny was created Duc de Sully and a Peer of France. The licentiousness of the King, and the power he allowed his mistresses to obtain over him, had continually thwarted Sully and undone much of the good they had together proposed and executed. The minister’s remonstrances were frequent, bold, and at times even violent; indeed, his whole life had been distinguished by an honest bluntness; but the propensities of the amorous monarch were incurable, and his faithful servant had the mortification of seeing him disgrace the last years of his life by an infatuation for the Princess of Condé. Henry had already determined on a war with his old enemies the Spaniards, when the flight of this lady with her husband, who took refuge in the states of the house of Austria, induced him to hurry on his preparations to attack both the Emperor and the King of Spain. Sully, at this time, had amassed forty millions of livres in the treasury of the state, and he engaged moreover to increase this sum to sixty or to seventy millions without laying on any new taxes. He had also provided the most numerous and magnificent corps of artillery that had ever been seen in Europe. But in the midst of these grand preparations Henry’s mind was agitated by his insane passion for the Princess of Condé, and oppressed by a presentiment of his fate. He was indeed told on every hand that plots were laid against his life; his romantic courage forsook him, he became absent and suspicious, and at last distrusted even his faithful minister. Sully now no longer saw his master except at short intervals, and lived, retired from the court, at the Arsenal, his official residence as Grand Master of the Artillery.