In the preliminary stages of army organization under Louis XIV., infantry troops were detailed as sappers, and instructed in these duties by the engineers.  This irregularity of service soon caused difficulties and losses, and the evils springing from it were so great, that Vauban urged the propriety of a separate organization.  In 1670 he officially recommended to the king to establish a regiment of twelve hundred sappers and ouvriers, and in a subsequent report on the value of these troops, used the following language:  “They would be useful in peace as well as in war, and would be the means of saving much in all fortifications where they should be employed.  In fact, I have not the least doubt that they would save annually to the king much more than their pay.  I assert all I have said on this subject with as much confidence as if I had seen the result; and I can, with the same certainty, add, that this small troop will be the means of saving large numbers of good engineers and brave officers and soldiers, from the stern necessity to which we are reduced of exposing, almost always, the laborers and those who support them; which necessity would not arise had we at command a sufficient number of this kind of workmen well instructed.  To such a degree have I felt the necessity of sappers, at every siege at which I have been present, that I have always had reason to repent of not having more urgently solicited the creation of this company.”

Such are the views of the greatest of military engineers, a man who fought one hundred and forty battles, conducted fifty-eight sieges, and built or repaired three hundred fortifications.  His anticipations of the usefulness of engineer troops were fully realized, and they have ever since received the most careful attention, and now form, as has just been shown, one of the most important and efficient arms in the French service.  The fortifications constructed by the engineers, as organized by Vauban, have ever since constituted one of the principal elements of the French military power.

In the wars of Napoleon there are innumerable instances in illustration of the delays and disasters attending the operations of armies not supplied with engineer troops; and, on the other hand, the advantages resulting from their services when properly organized and instructed.  We have already pointed out the influence which the fortifications in the hands of the French exerted on the results of these wars, and the fatal consequences to the Allies of neglecting these works of national defence.  Every student of military history will immediately call to mind the influence of Savona, Coni, Mondovi, Ceva, Govi, Alessandria, Tortona, Pizzighitone, Peschiera, Mantua, Palma-Nuova, Osopo, Klagenfurth, &c., in the campaigns of 1796-7; of Genoa, Port Bard, the fortifications of the Var, Ulm, Ingoldstadt, &c., in 1800; of Milan, Turin, Mantua, Roco d’Aufo, Genoa, Alessandria, &c., in 1805; the importance of Kehl, Cassel, Wesel, &c., to the French in 1806, and the fatal consequences to the Prussians in that campaign, of their total and culpable neglect of their own fortifications.