And in the now fast-failing light both lads dropped on their hands and knees and began a feverish search for what might very easily make all the difference to them between living and dying a horrible and painful death. Hound and round the fast-darkening cell they crawled, but not a sign of anything could they find, until Harry, who was searching a corner where the faint light from the grating could not reach, suddenly placed his hand upon something hard, which rolled under the pressure. Clasping it tight in his fist, he rushed to the grating and looked at the article. Yes, sure enough, it was a piece of paper wrapped round a pebble. He softly called Roger to his side, and, opening the folded missive, both began to read. And, as they read, both faces became several shades paler, and their hearts beat thickly. The note ran as follows:-- "I waited for some time below your window in the hope that you would drop an answer from it to my first letter; but I found that I was being watched, and had therefore to leave. How I shall get this present note to you I do not know, but if nobody is about I shall wrap it round a stone and try to throw it through your window. This is to tell you that Alvarez has decided to advance the day for your execution, which will take place on the day after to-morrow. Therefore you must act at once. I am myself in great danger through my attempts to help you, and if the date had not been altered should not have come until the third night from now. But there is no time to lose, so I must endeavour to come to you to-night. I may be discovered, but I must risk that. Now, attend well to what I am going to write. At midnight to-night, instead of three nights hence, I shall be here, underneath your window. You must at any cost let down a thin cord, or all my efforts will be vain. I will then attach to the cord several small files and a saw of fine temper. If the line is not strong enough to bear the weight I will tie a light line which I shall bring with me to yours; you will then haul that up first, and, making fast the end, you can then pull up the things I shall bring. If I have any more news then, I will also send up a letter to you. With the files and saw you must cut away all the bars of your grating except one. This will leave room for you to climb through. The one bar must be left to secure a stout rope to, so that you may slide down it. The work of cutting the bars will take you all to-morrow; so after my visit to-night I shall not come again until the time arrives for you to make your escape. Be very careful to work silently, or you will be discovered, for spies are everywhere. When the bars are cut, put them back in their places, so that if anyone enters your cell they shall not notice the change.