When his manifold energies were crippled by the war, he diverted his ability and abundant resources into privateering.

He was interested in at least eighty of the privateers out of Salem, invariably subscribing for such shares as might not be taken up by his fellow-townsmen.

He soon perceived that many of these craft were wretchedly unfit for the purpose and were easily captured or wrecked.

It was characteristic of his genius that he should establish shipyards of his own, turn his attention to naval architecture, and begin to build a class of vessels vastly superior in size, model, and speed to any previously launched in the colonies.

They were designed to meet the small cruiser of the British Navy on even terms and were remarkably successful, both in enriching their owner and in defying the enemy.
At the end of the war Elias Hasket Derby discovered that these fine ships were too large and costly to ply up and down the coast.