Presently the pines begin to grow less numerous and to be interspersed with the many varieties of oak for which the Sierra Madres will one day be noted, the most conspicuous of which is the _encino robles_, or everlasting oak, a beautiful tree with enormous leaves of a bright green color. The oaks increase in numbers as we descend, and the pines soon disappear; for we are getting out of the country of cold nights, which the conifers love so much. Presently a thorny mesquite is seen, and in half an hour we have traveled from Montana to Texas, in a climatic way. On the cumbra we jumped off from our mules and ran along by the half hour in the cool, fresh mountain air. Now five minutes brings out our handkerchiefs to wipe our perspiring brows. The northern cactus will soon mingle with the mesquite, and then the great pitahaya tells us we are on the verge of the tropics, while each tree in the orange orchard just below us can be made out, and after a few more turns on the twisting trails, even the yellow oranges on the bright green trees become distinct. Another half hour and we are on the level, while not that length of time has been added before palms are over our head, and the heat is almost unbearable to those who have been for weeks on the high mountain tops of the cool sierras. In a little over four hours we dropped from the land of the pine to the land of the palm, and this too on mule-back, a feat that could be performed in few countries outside of Mexico. We were now out of the land of wild forests and wild men, back again among Mexican civilization, but of a kind almost unknown to the outside world, although one of the richest mining districts and one of the oldest points of colonization on the North American continent. Our path was now lined with lovely, flowering, thorny shrubs, that stretched out and tried to scratch us, and often succeeded as we passed by. When we reached the little plateau of the first orange grove we rested awhile, and from here could look back to the cool place we had left but four short hours before. The way down from this resting place seemed steeper and longer than the first half of the journey; the heat became intense, the air throbbing and shimmering in the brilliant sunshine. Gayly colored paroquets and strange tropical birds went flitting past us and filled the air with their noisy calls and cries. The trail, however, had a persistent, unaccountable Indian method of keeping away from all shade, and wound among the thickest masses of thorny shrubs, which compelled us constantly to keep an eye on them, or be reminded in a manner more painful than pleasant. These, and the intense heat, made me long for the mountain life again. Although we had dropped from the crest of the range and land of pines to the land of palms, seven thousand feet, still we had many miles to wind up the great tropical barranca before we would reach the village.