110 WHAT MR. DARWIN SAW. 



ARGENTINE REPUBLIC. 



track of a thousand horses, they will soon guess the number 

 of mounted ones by seeing how many have cantered ; by the 

 depth of the other impressions, whether any horses were 

 loaded with cargoes; by the irregularity of the footsteps, 

 how far tired ; by the manner in which the food has been 

 cooked, whether the pursued travelled in haste ; by the gen- 

 eral appearance, how long it has been since they passed. 

 They consider a rastro ten days or a fortnight old quite re- 

 cent enough to be hunted out. 



In journeying from the Rio Negro to the Colorado we 

 came in sight of a famous tree, which the Indians reverence 

 as the altar of Walleechu. It stands on a high part of the 

 plain, and hence is a landmark visible at a great distance. 

 As soon as a tribe of Indians come in sight of it they offer 

 their adorations by loud shouts. The tree itself is low, much 

 branched, and thorny: just above the root it has a diameter 

 of about three feet. It stands by itself, without any neigh- 

 bor, and was indeed the first tree we saw ; afterward we met 

 with a few others of the same kind, but they were far from 

 common. Being winter, the tree had no leaves, but in their 

 place numberless threads, by which the various offerings, such 

 as cigars, bread, meat, pieces of cloth, etc., had been hung 

 upon it. Poor Indians, not having anything better, only 

 pull a thread out of their ponchos and fasten it to the tree. 

 Richer Indians are accustomed to pour spirits and mate (tea) 

 into a certain hole, and likewise to smoke upward, thinking 

 thus to afford all possible gratification to Walleechu. To 

 complete the scene, the tree was surrounded by the bleached 

 bones of horses which had been slaughtered as sacrifices. 



