5th. The lake of Tezcoco is that in which the ancient city of Tenochtitlan was built upon the spot at present occupied by the modern city of Mexico, whose walls, however, are now reached by a canal of nearly a mile in length from the western borders of this inland sea. The rivers Teotihuacan, Guadalupe or Tepeyacac, Papalotla and Tezcoco are voided into it. The difference between its water-mark and the level of Mexico, which in Humboldt's time was four feet and one inch has been found by recent measurements to be 18 inches more. Its superficial extent is about 10 square leagues, and its waters are plentifully impregnated with salt, supplying the material for numerous works which are rudely conducted. A thick crust or deposit of carbonate of soda constantly whitens the edges of this lake, which are left bare by the receding of the waters after they have been swept over the leeward shores by the strong winds that occasionally prevail in the valley. The deepest parts of the lake of Tezcoco never contain more than from 6 to 8 feet of water, while some portions are not covered by more than two or three feet. There are two springs of mineral waters in the neighborhood of the capital;--one at Guadalupe, three miles from Mexico, and another at El Peñon, a volcanic pustule which rises abruptly from the plain on the margin of the lake of Tezcoco. The temperature of the latter is quite high. The mode in which the valley is relieved from the danger of inundations in consequence of the rising of the waters of the lakes has been already noticed in a previous portion of this work.[56] The _desague_, according to recent reports, requires considerable repairs and improvements for the future security of the capital. The principal cities, towns and villages of this State are:--The national and state capital Mexico;--St. Angel, three leagues from the capital;--Tacubaya, about equidistant from Mexico, containing a number of beautiful residences, and an archiepiscopal Palace surrounded by groves and gardens; Santa Fé, Tlalpam or San Augustin de las Cuevas, four leagues south of the capital, situated upon the first slopes of the mountains, and filled with charming dwellings, to which the Mexicans occasionally retire during the warm season. It is in this town that the festival of St. Augustin is kept in the month of May, and during the three days of its celebration, Tlalpam is a scene of gaiety rarely equalled elsewhere on this continent. Rich and poor pour out from the capital to partake of the unrestrained amusements of the season, and thousands of dollars are lost at the gambling table or in the cock-pit, without which no Mexican festival is considered complete. The Mexican ladies appear at the balls which are given every night, or during the afternoon, on the green at the Calvario, and vie with each other in the splendor and variety of their dresses.