Unfortunately Turin is in the enemy's hands, but as the duchess's troops still hold the citadel, an advance could not very well be made until that has fallen.

Chivasso and Carignano are safe from any sudden attack.

There are other minor roads, but so long as these towns are in our hands and held by strong garrisons, an enemy advancing by any of these roads towards Susa would be liable to have their communications cut, and their convoys captured by parties from these fortresses.

It has long been a fixed idea in military operations that an army cannot advance as long as a town near the line of route is held by the enemy.

That idea is an erroneous one, and several times upon the Rhine we have gained successes by neglecting this rule and disregarding the towns, contenting ourselves with leaving a force sufficient to keep the garrison in check.
"The Spaniards, however, are slow to change their tactics, good soldiers as they are.