About four o'clock in the afternoon we arrived at a point where the river again narrowed to a width of about a mile; but some two miles farther on it again widened out, and changed its direction, trending away almost due east, or about at right angles to its former course; and this, according to the information in the skipper's possession, indicated that we were nearing our destination.  Drawing from his pocket a sketch chart which he had already consulted several times during our passage up the river, he again studied it intently for several minutes, carefully comparing the configurations delineated upon it with our actual surroundings; then, apparently satisfied with the result, he refolded the paper, returned it to his pocket, and directed the coxswain to bear away a couple of points toward a projecting point--which we afterwards discovered to be the western extremity of an islet--on the far side of the river.  As we approached the spot for which we were heading it became apparent that there were two islets instead of one between us and the river bank; and a quarter of an hour later the gig, with the rest of the flotilla following her, glided in between these two islets, and, lowering her sails, made the signal for the other boats to anchor.