The only hope of the Republicans, at this crisis, was Vauban's line of Flemish fortresses.

These alone saved France.

The strongholds of Lille, Conde, Valenciennes, Quesnoy, Landrecies, &c., held the Austrians in check till the French could raise new forces and reorganize their army.

"The important breathing-time which the sieges of these fortresses," says an English historian, "afforded to the French, and the immense advantage which they derived from the new levies which they received, and fresh organization which they acquired during that important period, is a signal proof of the vital importance of fortresses in contributing to national defence.

Napoleon has not hesitated to ascribe to the three months thus gained the salvation of France.