I had long wanted to go out to Huehuetoca to see the famous _tajo de Nochistongo_, the great cut in the mountains, the most interesting point of the wonderful system of draining the lakes of the Valley of Mexico. It was a problem to Aztec rulers, viceroys, and presidents, finally solved, like a good many other things, in the Diaz epoch--and always bound up with the joys and sorrows of the valley. The Lake of Texcoco, the largest of the six lakes, hospitably receives the waters of the other lakes to such an extent that once it was considered to have a "leaky bottom," draining down to the Gulf of Mexico. There were immense floodings of the city in old days, and in 1607 one so great that for several years the streets were traversed in canoes, and the saintly Archbishop of Mexico used to be poled and rowed about, distributing food to the starving. The Huehuetoca road runs out through Azcapotzalco, once a teeming Toltec and Aztec center, now only the haunt of Indians and an infrequent archæologist. Any and every turn of the soil there reveals traces of lost races. At the next town, Tlalnepantla, though we were all feeling more in the mood for general effects than detailed inspections, we did our duty and went into the interesting old church, finding it full not only of sacred relics, but of profane, in the shape of carved Indian stones and various sorts of monoliths. In the cold, ancient baptistry is a strange prehistoric cylindrical vase. There are still traces of the earthquake of several years ago, whose rendings revealed a wealth of buried objects. Several Indians, gathered about the motor as we came out, furtively drew from their knotted shirts some objects which properly belonged to the government--obsidian knives and a few masks, like those in the museum at San Juan Teotihuacan. We bought them out, and proceeded to Cuautitlan, the old posting-town I have written you about. Mr. de Soto says that tradition has it that here was born Juan Diego, the Indian to whom the Virgin of Guadalupe appeared. You see how interesting it is along these roads. Each step is always historic or legendary, as well as beautiful. The next village is Teoloyucan, where one branches off to go to Tepozotlan. Since leaving the posting-town we could see the belfry of the church looking pink and lovely against especially blue and lovely hills. The foreground was of maguey and maize fields stretching away to the mountains. Hedges of nopal, graceful willows and pepper-trees, and Indian life, mysterious, yet simple, living itself out on road and field. We were held up for quite a while by a dozen burros laden with fresh, shining skins bulging with pulque. A great deal of unnecessary prodding of the unfortunate animals went on, the usual audience appearing from the hedges at the noise.