Dominica

In 1778, a few handfuls of sand helped disable a British fort on Dominica.

Only fifteen years earlier, the island had been French, and many of its inhabitants still sided with France. On the evening before a French invasion, some of them walked up to the fort on the island’s southern tip and got the soldiers on guard drunk.

Then they filled the cannons’ touchholes, the small openings where the powder is lit, with sand.

The next morning the French arrived. The guns could not be fired, and the fort fell quickly. It was the first step in the capture of the island.

All it took was sand in exactly the wrong place.