46 CHEMICAL MANUEES. 



deposits differ considerably ; official data speak of 3,000,000 to 

 4,000,000 tons, other information represent the situation under 

 a less alluring aspect, and assert that the reserves are almost ex- 

 hausted. A road has been built, with great difficulty, across the 

 mountain to connect the deposit with the loading quay. At a mile 

 from the works the road divides into two — the one at a very rapid 

 incline leads to the harbour, whilst the other leads to a tent con- 

 structed on the edge of the plateau where the guano, which is lifted 

 there in sacks, is run into a shoot of 233 metres deep, which diverts 

 into a warehouse situated in the port. In the centre of the port dwell 

 the workmen, the overseers, the exporters, and the state govern- 

 ment employees. The latter weigh the guano, which is then con- 

 veyed in trucks on rails to the other extremity of the harbour, and 

 discharged into ships. The formation of Mejillones guano is 

 analogous to that of Baker guano. As the climate here also is 

 very dry, the absence of nitrogen can only supervene from the 

 possible contact of sea water. The volcanic nature of these 

 countries being granted, the periodical upheavals and sinkings of 

 the ground are known historical facts, and it is known that on 

 these occasions violent high waves are frequent. 



Mejillones Guano, like Baker guano, is a brown powder mixed 

 with more or less large friable lumps, consisting in part of phos- 

 phate of ammonia and magnesia. In the early days, this guano 

 was frequently mixed with granite chips, from the rocky bed on 

 which the deposits lie. But afterwards the importers installed 

 crushers and driers, which have enabled them to eliminate the 

 stones and to dispatch the guano as a uniform powder. Amongst 

 the numerous analyses published, that by Fresenius and Neubauer 

 is reproduced here. These chemists found in the sample dried at 

 100 the following results : — 



TABLE XXXVIII. —ANALYSIS OF MEJILLONES GUANO. 



Dr. Gilbert gives the following analysis : — 



