Bancroft (iv. 392, etc.) could only give a plan of the ruins based on the sketches of Mühlenpfordt as published by Carriedo, but the student will find a more careful one[1032] in Bandelier, who also gives detailed ones of the several buildings (pl. xvii., xviii.) * * * * * [Illustration: SACRIFICIAL STONE. After a photograph in Bandelier’s _Archæological Tour_, p. 67. See on another page, cut of the court-yard of the Museum, where this stone is preserved. Cf. Humboldt, pl. xxi.; Bandelier in _Amer. Antiq_., 1878; Bancroft, iv. 509; Stevens’s _Flint Chips_, 311. There is a discussion of the stone in Orozco y Berra’s _El Cuauhxicalli de Tizoc_, in the _Anales del Museo Nacional_, i. no. 1; ii. no. 1. On the sacrificial stone of San Juan Teotihuacan, see paper by Amos W. Butler in the _Amer. Antiq_., vii. 148. A cut in Clavigero (ii.) shows how the stone was used in sacrifices; the engraving has been often copied. In Mrs. Nuttall’s view this stone simply records the periodical tribute days (_Am. Ass. Adv. Sci. Proc._, Aug. 1886).] There is no part of Spanish America richer in architectural remains than the northern section of Yucatan, and Bancroft (iv. ch. 5) has occasion to enumerate and to describe with more or less fullness between fifty and sixty independent groups of ruins.[1033] Stephens explored forty-four of these abandoned towns, and such was the native ignorance that of only a few of them could anything be learned in Merida. And yet that this country was the land of a peculiar architecture was known to the earliest explorers. Francisco Hernandez de Cordova in 1517, Juan de Grijalva in 1518, Cortés himself in 1519, and Francisco de Montejo in 1527 observed the ruins in Cozumel, an island off the northwest coast of the peninsula, and at other points of the shore.[1034] It is only, however, within the present century that we have had any critical notices. Rio heard reports of them merely. Lorenzo de Zavala saw only Uxmal, as his account given in Dupaix shows. The earliest detailed descriptions were those of Waldeck in his _Voyage pittoresque et achéologique dans la province d’Yucatan_ (Paris, 1838, folio, with steel plates and lithographs), but he also saw little more than the ruins of Uxmal, in the expedition in which he had received pecuniary support from Lord Kingsborough.[1035] It is to John L. Stephens and his accompanying draughtsman, Frederic Catherwood, that we owe by far the most essential part of our knowledge of the Yucatan remains. He had begun a survey of Uxmal in 1840, but had made little progress when the illness of his artist broke up his plans. Accordingly he gave the world but partial results in his _Incidents of Travel in Central America_. Not satisfied with his imperfect examination, he returned to Yucatan in 1841, and in 1843 published at New York the book which has become the main source of information for all compilers ever since, his _Incidents of Travel in Yucatan_ (N.