In 1775 he commanded the Tuscan frigates in the Spanish-led Invasion of Algiers. Concerning the calamitous disembarkation in which the Spanish were drawn into a trap by the feigned retreat of the Algerines, the travel writer Henry Swinburne wrote that the Spaniards would have been "broken and slaughtered to a man ... had not Mr. Acton, the Tuscan commander, cut his cables and let his ships drive in to shore just as the enemy was coming on us full gallop. The incessant fire of his great guns, loaded with grape-shot, not only stop't them in their career but obliged them to retire with great loss."