I don’t want to steal any of Robert Patenaude’s thunder in the true tall tales department, but I’ll report the events of last night and let you decide the veracity of this account.

The conditions had grown too uncomfortable to continue sailing, so we had hove-to. The boat rocked constantly and occasionally was slapped by a wave or dropped off the end of one. But all in all, it was fairly comfortable.

Monica was in the port berth, which was the lee berth — or the downhill side of the boat. She was less likely to fall out of that berth than from the uphill, starboard berth.

As is our procedure, she kept her harness on, and, wrapping a tether around her body, she clipped on to a padeye behind the settee pads. The hope was that should an unusually large wave actually roll Robin, Monica would be stopped short of flying across the cabin and sustaining serious injury.

When I had completed work on deck, I came below. I wanted to sleep, but I chose against the starboard berth in favor of the cabin sole. There I unfolded a cockpit seat into its flat position as a mattress and placed it beside the saloon table.

I wrapped my tether around the table leg that is bolted to the floor, propped my head on a pillow, and quickly was asleep.

Then the banging started.

This was not the usual waves on the hull sound. It was a sharp banging.

I really didn’t want to get up and investigate, so I tried to think through the possible explanations. There was nothing inside the boat that could possibly come loose and make such a violent sound.

Monica suggested what I was thinking. Maybe the dinghy, rolled in its cover and lashed on the foredeck, was being lifted and dropped on the deck.

I knew that it had to be either the dinghy or one of the anchors had come loose and was slamming against the hull. Either one could be a disaster, so I got in my foul weather gear and climbed the companionway ladder.

I had left the deck light glowing so that we would be conspicuous in our hove-to position in the dark. So it was easy to see, when I went forward, that everything on deck was in its place and not moving.

I went back in my bunk and contemplated some more.

Certainly the inventory of the boat offered no additional suggestions. So I listened to the sound carefully. It was happening at least every minute, sometimes repeatedly.

Then I recalled someone telling of large sea creatures — fish and mammals — that slapped their big tails against boats for some inexplicable reason.

You will assume correctly that I will be telling this story when I get back to shore and will seek some confirmation that my explanation is plausible.

In time, the banging stopped, and we slept for five hours before rising after daybreak, rather refreshed.