One of the crew no doubt.

Are they going to let me out at last?
I can now hear voices.

A conversation is going on outside the door, but it is carried on in a language that I do not understand.

I shout to them--I shout again, but no answer is vouchsafed.
There is nothing to do, then, but wait, wait, wait! I keep repeating the word and it rings in my ears like a bell.
Let me try to calculate how long I have been here.

The ship must have been under way for at least four or five hours.