Simple lumps of earth, in lakes or rivers, carried away from the banks, have given rise to the invention of chinampas. The floating-gardens, of which very many were found by the Spaniards, when they first invaded Mexico, and of which many still exist in the lake of Chalco, were rafts formed of reeds, rushes, roots, and branches of underwood. The Indians cover these light and well connected materials with a black mould, which becomes extremely fertile. The chinampas sometimes contain the cottage of the Indian, who acts as guard for a group of floating gardens. When removed from one side of the banks to the other, they are either towed or are pushed with long poles. Every chinampa forms an oblong square about three hundred feet in length, and eighteen or nineteen feet broad. Narrow ditches, communicating symmetrically between them, separate these squares. The mould fit for cultivation rises about three feet above the surface of the surrounding water. On these chinampas are cultivated beans, peas, pimento, potatoes, artichokes, cauliflowers, and a great variety of other vegetables. Their sides are generally ornamented with flowers, and sometimes with hedges of rose-bushes. The promenade in boats, around the chinampas of the river Istracalco, is one of the most agreeable amusements that can be enjoyed in the environs of Mexico. The vegetation is extremely vigorous, on a soil which is continually refreshed with water. The _Hill of Chapoltepec_, near Mexico, was chosen by the young viceroy Galvez, as the site of a villa for himself and his successors. The castle has been finished externally, but the apartments were not completed when M. de Humboldt was here. This building cost the king of Spain more than L.62,000 sterling. With respect to the two great _lakes_, Tezcuco and Chalco, which are situated in the valley of Mexico, one is of fresh water, and the other salt. They are separated by a narrow range of mountains, which rise in the middle of the plain; and their waters mingle together, in a strait between the hills. On both these lakes there are numerous towns and villages, which carry on their commerce with each other in canoes, without touching the continent. FOOTNOTES: [3] From this place, Mr. Pike was conducted, through St. Antonio, in a north-westerly direction, to the territories of the United States; and he terminates the account of his travels at _Natchitoches_, on the southern bank of the Red river. Twenty-first Day's Instruction. MEXICO CONCLUDED. _A Description of some of the most important Places in Mexico._