Starvation remains.

Thirst remains.
Man-handling remains.

Truly, a man pent in a narrow cell is very helpless.
So the tapping ceased, and that night, when it was next resumed, I was all at sea again.

By pre-arrangement they had changed the initial letter of the code.

But I had caught the clue, and, in the matter of several days, occurred again the same initialment I had understood.