In order to accomplish this result, Bonaparte had purposely led Melas to believe that the Army of Reserve was intended to re-enforce the Army of Italy. Though Melas did not believe in the existence of an army of reserve, he knew that an effort was being made to organize troops in France, and he believed that they would eventually be sent to join Suchet. But the First Consul had no intention of doing what Melas expected him to do. It was necessary to the success of Bonaparte that he should conceal as much as possible his own purposes, in order to be able to surprise his adversary. In war it is always wise to lead the enemy to believe that an attack will be made in a different direction from that intended. "In whatever way strategy is employed," says Colonel Maurice, "surprise and concealment are essential to success. On this account it will continually happen, in selecting a line of operations or a scheme of campaign, that the most important point of all is to carry out just what an enemy does not expect. Very often successful campaigns, the method of which has been subsequently much criticised, have owed their success to the fact that, from a nice calculation of time and distance, the successful general has seen that he could carry through an operation dangerous in itself, but sure not to be the one expected by his opponent. For the same reason, in all the brilliant and successful efforts of strategic skill, steps have been taken beforehand to carry out the preliminary movements of an army in such a way as to leave an enemy up to the last moment uncertain in what direction the blow would be struck." Had Bonaparte marched into the middle part of the Austrian theatre of operations, it would have been necessary to cross the Alps over the Mont Cenis Pass. The objections to this plan were that the country lying between the Apennines and the Po contained the strong fortifications of Turin, Coni, Alessandria, and Tortona, which would enable the Austrians to hold Bonaparte in check long enough for Melas to concentrate his scattered forces. Furthermore, by entering Italy over this pass, Bonaparte would approach the centre of the Austrian line, which would enable the Austrians to concentrate against him more rapidly than if he moved against either flank of their position. Again: since the Austrians held the passes of the Apennines, they could delay the advance of the French on Genoa and continue the siege; or, if defeated, could fall back along the great highway leading from Piedmont through the Stradella Pass to Mantua. Though the great chain of the Alps seemed to present an almost impassable barrier to an army attempting to enter the extreme northern part of Italy from France or Switzerland, Bonaparte did not allow this fact to deter him from his great undertaking. There were several reasons why he adopted this plan. First: He knew that Melas was not expecting the French to enter this part of Italy.