Wells and reservoirs, completely walled with burnt clay, are found in Louisiana; near which are "systems," or groups of mounds so regular and strongly fortified, that they became the retreat of pirates and robbers who infested the rivers, greatly disturbing the early settlers, after the massacre of the Natchez Indians by the French. The Natchez built large dikes or ditches, and upon the counterscarp piled up huge ramparts, which they made almost impregnable, by having one side flanked by the slope of a hill, surrounded by precipices. They are sometimes situated on the level "bottoms."[3] In these cases one side invariably faces a creek or bayou, or is in its bend, making the creek serve as a formidable ditch, offering a serious impediment to an enemy's approach. The other two sides are protected by parallel walls or half moons, with gateways leading to the citadel. These walls have indications of having been faced with dry masonry. The east and west corners are generally flanked with a small oval mound. In these tumuli and mounds numerous ornaments and pottery were found by Dr. Dickeson, buried with the occupants, such as idols, clay stamps, mica mirrors, stone axes, and arrow heads, silver and copper ornaments, rings, beads of jasper, chalcedony, agate, &c., similar to those found in Peru and Mexico. Several pearls of great beauty and lustre, an inch in diameter, have been found. By an examination of the skulls, Dr. D. discovered that _dentistry_ had been extensively practised by this ancient people, as plugging the teeth, and inserting artificial ones, was common. In one instance, five artificial teeth were found inserted in one subject. Ovens were found containing pottery partially baked, three feet below the surface, with large trees covering them, exhibiting an age of upwards of five hundred years. Magazines of arrow points, in one instance a "wagon body full," (about twenty bushels), lying within the space of a few feet. In a small mound in Adams county, Dr. D. found three large jars holding upwards of ten gallons of arrow points elaborately finished; and three similar in dimensions and finish, have lately been received by Dr. Morton, of Philadelphia, from South Carolina. Carvings representing the English bull dog, the camel and lama, have been found by Dr. Dickeson, from forty to sixty feet below the surface of the mound. The bricks, to which allusion has been made, are of various colors; some of a bright red, others dark brown, various shades of purple and yellow. Forty stamps of baked clay, containing a variety of figures used for stamping their skins. Pieces of coin, two of which found near Natches, had the figure of a bird on one side, and on the reverse an animal.