Slidell and Mason went to Europe in January, 1862. This was perhaps the darkest and most critical period for the cause of the Union during the great struggle. The Commissioners carried letters with them showing the inefficiency of the blockade of the Southern ports, the great disadvantages and losses suffered by England and France through cutting off the cotton supplies, and setting forth the enormous advantages that would result if free trade with the Confederacy were established. These were strong arguments to arouse the spirit of commercial selfishness in favor of the South. The ambitious designs of Napoleon were of a very towering and extensive character. He not only expected to recover Louisiana, which his uncle in an hour of necessity had sold to the United States, but he aimed at the restoration of the entire old colonial empire of France on this continent. The Emperor was thoroughly posted in the affairs of this country. It seems that while he had resided in a small room in Hoboken, and took his meals at a twenty-five cent restaurant, paying for them with money borrowed from French patriots, on the very slim prospect of reaching the throne of France, he made the best use of his time, and he had studied the history and geography of the United States and Canada with great care and accuracy. In justice to his character for gratitude, however, it must be said, in passing, that, like young “Corneel” Vanderbilt, he paid all the money he borrowed, and placed some of his New York and Hoboken creditors in good positions at the Tuileries, under the Second Empire. He never forgot a favor nor forgave an injury. The Emperor’s knowledge of American affairs, as well as his ambitious designs, were briefly, but at the same time very fully disclosed, in conversation with Mr. Benjamin, at the Villa Eugenie, at Biarritz. “He turned with peculiar and undisguised eagerness,” said Mr. Benjamin, “to the Mexican question. He knew the very number of guns on the Morro, the sums the United States had spent on the fortifications in Florida, the exports and imports of Galveston and Matamoras, in fact everything which well informed local agents could have reported to an experienced statesman eager for information. He examined me again on Texas and its population, the disposition of the French residents, the tendencies of the German colonists, the feeling on the Mexican frontier. He observed that Louisiana was nothing but French at the bottom. I was fully persuaded that he proposed to seek in Mexico a compensation for the lost colonies in the West Indies, which, he said, could not be recovered, ‘_sans nous brouiller avec nòs allies_,’ (without embroiling us with our allies). He insisted upon it that France must, sooner or later, have a foothold (_pied à terre_) on the Florida coast, for the purpose of protecting her commerce in the Gulf, for, he added, ‘_Nous ne voulons pas d’un autre_ _Gibraltar de ce côté là_,’ (we don’t want another Gibraltar on that side.”)