In some of the ruins, and especially at Copan, there are clusters of four-sided stone pillars or obelisks varying from twelve to over twenty feet high. These are elaborately sculptured, and show human figures, ornamental designs, and many inscriptions. One or two statues have been discovered, and a statuette twelve inches high is described; “it is made of baked clay, very hard, and the surface is smooth as if coated with enamel.” At Palenque are remains of a well-built aqueduct; and near the ruins, especially in Yucatan, are frequently found the remains of many finely constructed aguadas or artificial lakes. The bottoms of these lakes were made of flat stones laid in cement, several layers deep. In Yucatan traces of a very ancient paved road have been found. This road ran north and south, and probably led to cities in the region now covered by the great wilderness. It was raised above the graded level of the ground, and made very smooth. These antiquities show that this section of the continent was anciently occupied by a people admirably skilled in the arts of masonry, building, and architectural decoration. Some of their works can not be excelled by the best of our constructors and decorators. They were highly skilled, also, in the appliances of civilized life, and they had the art of writing, a fact placed beyond dispute by their many inscriptions. A more particular account of some of these ruins will be given in the next chapter. Among the more important works relating to them are those of Stephens and Catherwood, some of the volumes of Mr. Squier, Frederick Waldeck’s work, and a recent French volume by Desiré Charnay, which is accompanied by a folio volume of photographs. Palacios, who described Copan in 1576, may properly be called the first explorer. A brief account of Palenque was prepared by Captain Del Rio in 1787, and published in 1822. Captain Dupaix’s folios, in French, with the drawings of Casteñada, contain the first really important memoir on these ruins. It was prepared in 1807, detained in Mexico during the Mexican Revolution, and finally published at Paris in 1834-5. The volumes of Brasseur de Bourbourg are valuable. They relate chiefly to matters not always understood, and seldom discussed with care, by those who merely visit and describe the monuments, such as the writing, books, and traditions of the ancient Mexican and Central American people. His style is diffuse, sometimes confused, and rather tedious; and some of his theories are very fanciful. But he has discovered the key to the Maya alphabet and translated one of the old Central American books. No careful student of American archæology can afford to neglect what he has written on this subject. V. MEXICO AND CENTRAL AMERICA.