PARALLEL KOADS. 



7 



their general width is from twenty to fifty yards. 

 There are three distinctly characterized sets, and 

 a lower one, which is indistinct when approached, 

 but, when viewed from a distance, is evidently of 

 the same character with the others. These roads 

 are improperly called parallel : horizontal would 

 be a more correct term : the planes in which they 

 lie are indeed parallel to one another, and thence 

 has arisen the erroneous expression. 



The uppermost one lies probably three or four 

 hundred feet above the level of the sea ; and two 

 hundred and fifty from the bottom of the valley ; 

 the next twenty yards lower ; and the lowest of 

 the distinct set about ten yards still lower. These 

 distances are loosely estimated, and may be wrong ; 

 for it is very difiicult to determine heights or dis- 

 tances in a country quite new, and without natu- 

 ral and determinate objects of comparison. There 

 being neither trees, houses, cattle, nor men in 

 this valley, our estimates were made entirely by 

 guess. This, however, does not affect the gene- 

 ral question, but only the dimensions. When at 

 any time we found ourselves on one of these pa^ 

 rallel roads, we saw, upon looking across the vaU 



