Again, if the infantry be previously weakened, or thrown into disorder by the fire of batteries.

The charge of the Russian cavalry at Hohenfriedberg, in 1745, is a remarkable example of this kind.
Cavalry should always be immediately sustained in its efforts either by infantry or other bodies of horse; for as soon as the charge is made, the strength of this arm is for a time exhausted, and, if immediately attacked, defeat becomes inevitable.

The charge of the cavalry of Ney on Prince Hohenlohe at the battle of Jena, and of the French horse on Gossa at Leipsic, are fine examples of the successful charges of cavalry when properly sustained.

Kunnersdorf and Waterloo are examples of the disastrous consequences of leaving such charges without support.
The choice of the field of battle is sometimes such as to render cavalry almost useless.

Such was the case at the battle of Cassano, between the Duke of Vendome and the Prince Eugene.