mule.  As a matter of fact, although it is only a two days’ journey, pack animals’ backs are not built to survive the strain of carrying pieces of machinery weighing five hundred pounds over a desert plateau up to an altitude of 4000 feet.  Mules brought the machinery from the coast to the brink of the canyon, but no mule could possibly have carried it down the steep trail into Caraveli.  Accordingly, a windlass had been constructed on the edge of the precipice and the machinery had been lowered, piece by piece, by block and tackle.  Such was one of the obstacles with which these undaunted engineers had had to contend.  Had the man who designed the machinery ever traveled with a pack train, climbing up and down over these rocky stairways called mountain trails, I am sure that he would have made his castings much smaller.

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Figure

Mr. Tucker on a Mountain Trail near Caraveli
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Figure

The Main Street of Chuquibamba
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It is astonishing how often people who ship goods to the interior of South America fail to realize that no single piece should be any heavier than a pack animal can carry comfortably on one side.  One hundred and fifty pounds ought to be the extreme limit of a unit.  Even a large, strong mule will last only a few days on such trails as are shown in the accompanying illustration if the total weight of his cargo is over three hundred pounds.  When a single piece weighs more than two hundred pounds it has to be balanced on the back of the animal.  Then the load rocks, and chafes the unfortunate mule, besides causing great inconvenience and constant worry to the muleteers.  As a matter of expediency it is better to have the individual units weigh about seventy-five pounds.  Such a weight is easier for the arrieros to handle in the loading, unloading, and reloading that goes on all day long, particularly if the trail is up-and-down, as usually happens in the Andes.  Furthermore, one seventy-five-pound unit makes a fair load for a man or a llama, two are right for a burro, and three for an average mule.  Four can be loaded, if necessary, on a stout mule.

The hospitable mining engineers urged us to prolong our stay at “La Victoria,” but we had to hasten on.  Leaving the pleasant shade trees of Caraveli, we climbed the barren, desolate hills of coarse gravel and lava rock and left the canyon.  We were surprised to find near the top of the rise the scattered foundations of fifty little circular or oval huts averaging eight feet in diameter.  There was no water near here.  Hardly a green thing of any sort was to be seen in the vicinity, yet here had once been a village.  It seemed to belong to the same period as that found on the southern slopes of the Parinacochas Basin.  The road was one of the worst we encountered anywhere, being at times merely a rough, rocky trail over and among huge piles of lava blocks.  Several of the larger boulders were covered with pictographs.  They represented a serpent and a sun, besides men and animals.