Much was sacrificed to bring off these valuable materials for making clamps and fastenings, but, as Segur observes, that exertion '_sauva l'armee_.'" But it is not always in the possession of a thing that we are most likely to appreciate its utility; the evils and inconveniences resulting from the want of it not unfrequently impress us most powerfully with its importance and the advantages to be derived from its possession.

A few examples of this nature, drawn from military history, may be instructive.

We need not go back to the disastrous passage of the Vistula by Charles XII., the failure of Marlborough to pass the Dyle, and Eugene to cross the Adda in 1705, nor of the three unsuccessful attempts of Charles of Lorraine to cross the Rhine in 1743.

The wars following the French Revolution are sufficiently replete with useful instruction on this subject.[39] [Footnote 39: Before recurring to these, it might be useful to give one example, as it is often referred to, in the campaign of 1702.

It was deemed important for the success of the campaign to attack the Prince of Baden in his camp at Friedlingen.