1 adjectives to describe sledgehammers

The waves pounded like Titanic sledgehammers against the vessel's quivering timbers; the gale roared a deep diapason through the cordage; and the regular thud, thud, thud of the pumps, and the long melancholy whistling of the wind through the blocks, filled our minds with dismal forebodings, and banished all inclination for sleep.

1 adjectives to describe  sledgehammers