There was no regularity in the sea.

It seemed to rise suddenly in heaps, now striking the ship on one side, now on another, and pouring sheets of water over her bulwarks.

The motion of the vessel was so tremendous that even Bill Hardy and the older seamen could only move along with the greatest difficulty to carry out the orders of the captain; while Reuben clung to the shrouds, now half buried in water, now almost hanging in the air, with the sea racing along under his feet.
As yet no more sail had been put upon her, for there was no following sea.

Although running almost before the gale, a slight helm was kept upon her, so as to edge her out from the centre of the storm; and the second circle of the compass took more than twice as long as the first to complete, although the vessel was proceeding with equal speed through the water.
Hour after hour the sea got up--a wild, cross, broken sea--and the motion of the vessel was so terrific as to be almost bewildering to the oldest hands.

There was none of the regular rise and fall of an ordinary sea; the vessel was thrown with violent jerks, now on one side, now on the other; now plunging her bow so deeply down that she seemed about to dive, head foremost, beneath the waves; now thrown bodily upwards, as if tossed up by some giant hand beneath her.