It is impossible with our present knowledge to form an estimate of the civilization of the Aztecs at their highest point. The reports given by the Spaniards at the time of the conquests are not to be relied upon, as they paint in the exaggerated colors they thought most likely to give glory to their own achievements. Unfortunately they felt called upon to destroy most of the picture-writings they found, which would have been as valuable in forming an opinion of the manners and customs of the race they depicted, as the volumes we find in European libraries are to enlighten us upon the manners and customs of contemporary races in Europe. The Aztecs knew no alphabet, but instead of letters they used certain signs or hieroglyphics by which they wrote on every subject--religion, history, geography, poetry, feasts, famines, wars, and the arts of peace. This fashion of writing was handed down from father to son, and taught in colleges or by the priests. The artists who executed the manuscripts were treated with general consideration, and the sovereign even paid them honor. They worked on paper made of the fibre of the maguey, or on linen cloth, with a sort of pen like the stylus of the Romans. The colors were procured from vegetable dyes, in general. They had little variety of tint, but were vivid and permanent. These paintings, of which several of the small remnant in existence of the great quantity destroyed by the Conquistadores are in the museum at Mexico, are extremely interesting, both as works of art from a point of view entirely different from our European prejudices, and also as recording events with wonderful simplicity and directness. The one called the Wanderings of the Aztecs, is absolutely authentic, and is wholly interpreted. It is forty-eight feet long and nine inches wide done on maguey paper, all in black, with no other colors, except that the line of travel is marked in red. This painting gives the route of the Aztecs, from their departure from Aztlan until their arrival in the valley of Mexico. On an island, in the land of Aztlan, stands a teocalli, like the temples of worship in Mexico. The chronology year by year is given, and the various halts made by the wanderers, with the principal events that befell them. A short piece at the end is torn off and missing, which probably depicted the founding of Tenochtitlan. Another painting depicts a range of mountains among which is one pouring forth smoke from its summit. On the left is a city entirely surrounded by water, with the cactus growing on the rock, which always signifies Tenochtitlan. The mountain doubtless in Popocatepetl, which by its name signifies Hill that gives Smoke. Another painting gives the chronology of the kings of Mexico and Texcuco; it is long, stretching half across the large room of the museum in which it is exhibited. [Illustration: COURT OF THE MUSEUM AT MEXICO.]