as polished as glass, and, whether wet or dry, is slippery to the tread.  Walking over these jagged surfaces of limestone is destructive to any shoes.  A single afternoon of this will do more wear than a month of ordinary use.  Troublesome as these limestones are, as roads, they are ever interesting, because the masses by the roadside present the most astonishing and beautiful forms of waterwear; upon a mass eight or ten feet across, there will be worn a system of ridges and intervening channels, which, in miniature, seems to reproduce the orographic features of the whole country.

[Illustration:  WOMEN WITH BABIES; SAN JUAN ZAUTLA]

[Illustration:  CAIRN, ON ROAD TO COIXTLAHUACA]

While we were passing over one of these limestone stretches, a little before reaching the summit, we found a spot of unusual difficulty.  The two pack animals were together, one tied to the tail of the other; the second had several times acted badly, but in passing over this bit of road, he jumped and plunged, so that his pack loosened and slid to one side.  Plunging, kicking, and falling, he dragged down the unfortunate beast to whose tail he was tied; the old rope tugged and creaked, and, for a moment, we expected to see the very tail of the forward animal pulled out, and both packs destroyed by the struggling beasts.  Fortunately, at this moment, the rope itself broke.  The forward animal was loosened and quickly quieted; but the other one kicked and struggled, with our load of plates and developing trays under him.  Quickly cutting the ropes that held the burden, we tried to release the animal, but it lay exhausted, and, for a moment, we thought it dead.  Really, however, it was not hurt at all, and the loads themselves appeared undamaged.  The burdens having been repacked, we again started on the journey.  At several places on this road, we had noticed cairns, or heaps of pebbles.  On inquiring from Don Manuel—­the funny little man, who had the animals in charge—­we learned that every Chocho indian passing the place adds a pebble to the heap, to secure good luck and insure his safe return home.  At the summit, we found one of these piles of stone surmounted by a cross, and learned that when the Chochos reach this spot, they always stop, repeat a prayer, and dance for good health and fortune before the cross.  It was now almost dark.  Soon we saw the downward slope, at the foot of which Huauhtla lay.  We hastened down the slope, passing through a grove of oak trees, heavily loaded with bromelias; at the foot of the slope, we crossed a stream of clearest water, bordered with handsome cypress trees, and passing several houses, came to the one where we planned to stop for the night.  It was now dark.  There was no opportunity for sleeping in the hut, and so we prepared to lie down outside.  The people in the house prepared tortillas and beans, and, after eating, we rolled up in our blankets and lay down on some dried corn-husks on