This was about eight o'clock. I went to bed, and about twelve I was roused by O'Brien, who told me to dress myself carefully, and come down to him in the yard. It was some time before I could find O'Brien, who was hard at work; and, as I had already been made acquainted with all his plans, I will now explain them. At Montpelier he had procured six large pieces of iron, about eighteen inches long, with a gimlet at one end of each, and a square at the other, which fitted to a handle which unshipped. For precaution he had a spare handle, but each handle fitted to all the irons. O'Brien had screwed one of these pieces of iron between the interstices of the stones of which the wall was built, and sitting astride on that, was fixing another about three feet above. When he had accomplished this, he stood upon the lower iron, and, supporting himself by the second, which about met his hip, he screwed in a third, always fixing them about six inches on one side of the other, and not one above the other. When he had screwed in his six irons, he was about half up the wall, and then he fastened his rope, which he had carried round his neck, to the upper iron, and lowering himself down, unscrewed the four lower irons; then, ascending by the rope, he stood upon the fifth iron, and, supporting himself by the upper iron, recommenced his task. By these means he arrived in the course of an hour and a half at the top of the wall, where he fixed his last iron, and making his rope fast, he came down again. "Now, Peter," said he, "there is no fear of the sentries seeing us; if they had the eyes of cats, they could not until we are on the top of the wall; but then we arrive at the glacis, and we must creep to the ramparts on our bellies. I am going up with all the materials. Give me your haversack--you will go up lighter; and recollect, should any accident happen to me, you run to bed again. If, on the contrary, I pull the rope up and down three or four times, you may sheer up it as fast as you can." O'Brien then loaded himself with the other rope, the two knapsacks, iron crows, and other implements he had procured; and, last of all, with the umbrella. "Peter, if the rope bears me with all this, it is clear it will bear such a creature as you are, therefore don't be afraid." So whispering, he commenced his ascent; in about three minutes he was up, and the rope pulled. I immediately followed him, and found the rope very easy to climb, from the knots at every two feet, which gave me a hold for my feet, and I was up in as short a time as he was. He caught me by the collar, putting his wet hand on my mouth, and I lay down beside him while he pulled up the rope. We then crawled on our stomachs across the glacis till we arrived at the rampart. It was some time before O'Brien could find out the point exactly above the drawbridge of the first ditch; at last he did--he fixed his crow-bar in, and lowered down the rope.