1 6 R. A. F. PENROSE, JR. 



in the extreme southern part of the province of Antofagasta, is the 

 Taltal or Cachinal Pampa, where large quantities of nitrate are also 

 produced. A railway connects this district with the coast at Taltal, 

 which is a prosperous seaport in the southern part of the province of 

 Antofagasta and the shipping-point for the Taltal district. 



Though most of the nitrate deposits of Chile are in the provinces 

 of Tarapaca and Antofagasta, yet some have been found to the north 

 and south of these limits. As yet, however, they have not become 

 of great importance. In the province of Tacna, to the north of the 

 province of Tarapaca, several small pampas represent a northerly 

 continuation of the general pampa region, and a few small nitrate 

 deposits have been found there. South of the province of Antofa- 

 gasta, isolated nitrate deposits have been reported in places in the 

 northern part of the province of Atacama, but the extent of the deposits 

 is not yet well defined. 



ORIGIN OF THE NITRATE DEPOSITS OF CHILE 



The discussion of the origin of the nitrates of Chile involves 

 chiefly the source of the nitrogen, and many suggestions have been 

 advanced to explain its presence, but its derivation from organic 

 matter, and especially from guano, seems the most probable hypothe- 

 sis. Among some of the other hypotheses that have been suggested 

 may be mentioned the following: 



It is a well-known fact that electric storms have the power of caus- 

 ing the oxidation of the nitrogen of the air with the formation of 

 nitric acid. It has been suggested by some that such storms in the 

 Andes have generated nitric acid, which, coming in contact with the 

 limestone found in places in the mountains, has formed calcium 

 nitrate; and that this has in turn been converted to sodium nitrate 

 by contact with sodium salts found in the pampa region. 



It has also been suggested that the nitrogp'^. of the nitrates was 

 derived from nitrogenous fumes from volcano.^ in the Andes. 



A. Pissis' quotes authority to show that alkaline carbonates 

 have the power "of transforming atmospheric nitrogen into nitric 

 acid in the presence of other oxidizable matters." He points out that 

 the decay of feldspar in the rocks of the region has supplied a source 



I Nitrate and Guano Deposits in the Desert of Atacama, London, 1878, p. 16. 



