Rio is supplied with water by an aqueduct which comes from far up among the mountains, its chief source being a romantic and forest-surrounded spot, called the "Mother of Waters."  The actual channel which conveys sufficient water to supply so large a city as Rio is only nine inches wide and nine and a half deep.  The precious fluid, however, comes rushing down with great rapidity, and thus quickly fills all the reservoirs below.  It is conveyed from its mountain-source sometimes across valleys on high massive arches, sometimes in the interior of a thick wall-like structure, and sometimes underground.  The channel has for its whole length an arch above it of sufficient height and width to enable a man to walk upright along it.  Altogether, we agreed that Rio if it were not for the slaves and the monks, and the want of drains, would be a very civilised city.  Never did sight-seers get over the ground faster than we did, or make better use of their eyes.  I ought to have mentioned that steamers ply in various directions in the harbour of Rio.  Our friend proposed a trip up the country, which would last during the few days we had to spare.  We started in one of the smallest of the steamers, and went up the River Macacu.  One thing struck us--a boat laden with slaves, which had been landed on the opposite shore, and were being smuggled into the city.  We went on shore at the small town of Porto Sampaio, and thence on mule back about fifteen miles, to the country-house of a Brazilian gentleman, our friend's friend.  We four had a room to ourselves--a large, roughly built apartment.  Scarcely were we all in bed, and the light out, when, just as I had dropped asleep, down came something on my nose.  I started up, and there appeared to be a tremendous clattering and pattering about the room.