By the convention of Fontainebleau, the emperor was entitled to send forty thousand men into the northern parts of Spain. The right thus acquired was grossly abused, but the exercise of it being expected, created at first but little alarm. It was different on the eastern frontier: Napoleon had never intimated a wish to pass forces by Catalonia; neither the treaty nor the convention authorized such a measure, nor could the pretence of supporting Junot in Portugal be advanced as a mask. Nevertheless, so early as the 9th of February, eleven thousand infantry, sixteen hundred cavalry, and eighteen pieces of artillery, under the command of general Duhesme, crossed the frontier at La Jonquera, and marched upon Barcelona, leaving a detachment at the town of Figueras, the strong citadel of which commands the principal pass of the mountains. Arrived at Barcelona, Duhesme prolonged his residence there under the pretext of waiting for instructions from Madrid, relative to a pretended march upon Cadiz; but his secret orders were, to obtain exact information concerning the Catalonian fortresses, dépôts, and magazines,--to ascertain the state of public feeling,--to preserve a rigid discipline,--scrupulously to avoid giving any offence to the Spaniards, and to enter into close communication with marshal Moncey, at that time commanding the whole of the French army in the north of Spain. The political affairs were even then beginning to indicate serious results, and as soon as Duhesme’s report was received, and the troops in the north were in a condition to execute their orders, he was directed to seize upon the citadel of Barcelona, and the fort of Monjuick. The citadel was obtained by stratagem; the fort, one of the strongest in the world, was surrendered by the governor Alvarez. That brave and worthy officer, knowing the baseness of his court, was certain that he would receive no support from that quarter, and did not resist the demand of the French general, who having failed to surprise the vigilance of the garrison, impudently insisted upon a surrender of the place. Alvarez consented to relinquish his charge, although he felt the disgrace of his situation so acutely that, it is said, he had some thoughts of springing a mine beneath a French detachment during the conference; but his mind, unequal to the occasion, betrayed his spirit, and he sunk, oppressed by the force of unexpected circumstances.