This important result could only be achieved by a nation confident of controlling the communications by its sea power, to which the happy issue must wholly be ascribed, and which had another signal illustration in the timely conveying of four thousand American troops to reinforce the English ranks, terribly wasted by battle and fever.

It is said that only twenty-five hundred serviceable fighting men remained on foot when the city fell.
While the long reach and vigor of England's sea power was thus felt in the West Indies, it was receiving further illustration in Portugal and in the far East.

The allied crowns in the beginning had invited Portugal to join their alliance against those whom they had taken to calling the "tyrants of the seas," reminding her how the English monopoly of her trade was draining the country of gold, and recalling the deliberate violation of her neutrality by the fleet under Boscawen.

The Portuguese minister of the day well knew all this, and keenly felt it; but though the invitation was accompanied by the plain statement that Portugal would not be allowed to continue a neutrality she could not enforce, he judged rightly that the country had more to fear from England and her fleet than from the Spanish army.

The allies declared war and invaded Portugal.