In August, when there were a few young ducks about, the pond used to remind me in places of the tropical lakes we heard so much of after the explorers got through the portentous continent, on account of the growth of aquatic weeds, the quantity and extent of which no one would credit who had not seen them. No wonder the explorers could not get through the papyrus-grown rivers and lakes, for a boat could hardly be forced through these. Acres upon acres of weeds covered the place, some coming up from a depth of twelve feet. Some fish are chiefly on the feed in the morning, and any one who has the courage to get up at five will find them ravenous. We often visited the place a little after that hour. A swim was generally the first thing, and I mention a swim because it brings me to the way in which this mere pond illustrated the great ocean which encircles the world. For it is well known that the mighty ocean is belted with currents, the cold water of the Polar seas seeking the warmth of the Equator, and the warm water of the Equator floating--like the Gulf Stream--towards the Pole, floating because (I think I am right) the warm water runs on the surface. The favourite spot for swimming in our pond was in such a position that a copse cast a wide piece of water there into deep shadow all the morning up till ten o'clock at least. At six in the morning this did not matter, all the water was of much the same temperature; having been exposed to the night everywhere, it was cold of course.