THE POZO STONE. 405 



because the currents of air are deprived of their humidity in crossing 

 the Andes. On the other hand, the winds from the Pacific blowing 

 from the cool sea, and being of low temperature, their scanty- 

 vapour is dissipated by the heat radiated from the land without 

 leaving a drop of moisture to refresh the thirsty soil."* This 

 absence of rain in Peru has a most conserving action on archaeo- 

 logical objects, and is the reason why the incisions on the stone 

 are so perfect, although undoubtedly worked so long ago. Mr. L. 

 Fletcher, F.R.S., Keeper of the Minerals in the British Museum, 

 in an article on " Meteorites from the Desert of Atacama and its 

 neighbourhood," in the Mineral ogical Magazine for October, 1889, 

 says, "The air of the Desert is so clear that a four hour's journey 

 really meant a couple of days of hard travelling; Harding states that 

 'a page of ordinary note paper if doubled over and pressed with a 

 paper knife will break in two when opened out.' In so dry a 

 climate a mass of meteoric iron of moderate size will endure for 

 countless ages without rusting away." 



Though the incised characters have not been materially acted 

 upon by the weather, the body of the stone has been subject to its 

 long continued influence; and is weathered in such a fashion that 

 not a single person who has visited the country can help me to a 

 specific explanation of how it has been accomplished. It has 

 been suggested that dew may have had some action on the stone, 

 we know fogs are common on the Peruvian coast, but of the 

 quantity of dew in the rainless region I cannot speak, my idea, 

 however, is that greater volumes of water have had to do with this 

 weathering than dew would furnish. The weathering on the stone 

 is of two degrees, mild and intense. In shape the stone is roughly 

 five-faced, and on four of the five faces it has weathered only 

 sufficiently to round off those angularities which the stone would 

 possess when it fell from some escarpment in the mountains. 

 This is exactly what happens to blocks of limestone in Britain. 

 On the surface of the Pozo Stone, as on weathered fossiliferous 

 rocks at home, organic remains stand up in ridges and points left 

 by the quicker weathering of the softer matrix ; the difference in 

 the molecular arrangement of the organic and inorganic limes 

 being the chief cause of this. 



* " Central, West Indies and South America," W. H. Bates, 3rd edition. 



