The position of the man on watch at this point was just at the left oblique from the other men, say about ten paces, and very near to a tree which stood apart from the rest of the forest, a scraggy pine of second growth, not very tall, but thick and heavy, with its limbs starting from the trunk as low as eight feet from the ground. I stood near this tree, within reach of it by a leap. Our nearest vedette posts, right and left, were a hundred yards from me--the one on the left being in the woods, that on the right in the open. The country called the Peninsula is low and flat and very swampy in many parts, and the great quantity of rain that had now fallen for days and days had rendered the whole land a loblolly, to use a common figure. I saw that just in front of me, about thirty yards, there was a shallow ravine, and I began to think that it was possible for an enterprising squad of rebels to sneak through this ravine and get very near us before we knew it, and perhaps capture us; such things had been done, if the truth was told, not only by the rebels, but by many other people at war. Beyond the ravine were the Confederates, their skirmish line about three hundred yards beyond it, and their nightly vedette posts nobody knew where, for they used similar economy to ours in withdrawing their vedettes in the day. The Doctor's talks, many of which I can but barely mention, had opened my eyes a little to the possibility of accurate inferences, that is to say, his philosophy of cause and effect, or purpose, as he liked better to call it, had been urged upon me so frequently and so profoundly that I had become more observant; he had made me think of the relations of things. Philosophy, he had said, should be carried into everyday life and into the smallest matters; that was what made a good fisherman, a good farmer, a good merchant, and a good soldier, provided, he had added, there could be such a thing. This ravine, then, had attracted me from the first. I saw that it presented opportunity. A few rebels might creep along it, get into the woods, make prisoners of the vedettes on several posts, and then there would be a gap through which our skirmish line might be surprised. I went quietly forward in the edge of the woods until I stood near the ravine, and examined it as well as I could for the darkness. It did not extend into the forest, for the roots of the trees there protected the soil from washing away. The undergrowth at my left was not very dense; I judged that in daylight one could see into the forest a hundred yards or more. At my right, the gully began and seemed to widen and deepen as it went, but nothing definite could I make out; all was lost in the night. My examination of the spot had been made very quickly, for I was really transgressing rule in leaving my post, even for a more forward place but thirty yards away, and I was back at my tree in less than a minute.