Why a fleet could bring exceptional artillery ashore

Did Cochrane have more and heavier artillery at Guadeloupe than Napoleon had at Waterloo?

Yes, and the comparison illustrates how fleets concentrate artillery and can exploit predictable land routes and fixed shore targets.

A viewer observes that Cochrane may have controlled more and heavier guns than Napoleon used at Waterloo. Modern navies likewise concentrate considerable firepower in a small number of hulls. By shell weight and rate of fire, Royal Navy deck guns collectively amount to several field-artillery batteries before missiles and carrier aircraft are counted. Land forces also tend to move through flat ground, bridges, and other predictable approaches that can be registered in advance. Ships at sea can maneuver in any direction, making them harder gunnery targets than many shore positions. Naval artillery can therefore have disproportionate effect when the fleet is close enough to support an army.