Guano 



Part of the nitrogen was soluble in water and 

 directly assimilable by plants, the rest was in a form 

 easily converted into assimilable combinations. 

 There was a little in the actual form of nitrate, 

 and the rest was urate and phosphate of ammonia, 

 etc. 



A quarter of the phosphoric acid was soluble 

 in water, the remaining three-quarters being in a 

 tricalcic form, but certainly in a state of assimilability 

 comparable to, if not better than, that of bones. 



The guano of the Chincha Islands was exhausted, 

 but the reputation of its value was firmly established. 

 Hence guanos of poorer quality were imported, 

 coming from many parts of Peru, Bolivia, Colombia, 

 Patagonia, the coast of Australia, South-West 

 Africa, and the Pacific Islands. These were not so 

 old as the first, therefore not so concentrated, and 

 under a less assimilable form, coming some from 

 regions of little rain, others from more rainy 

 regions ; mixed with feathers, refuse of fish, and 

 bones of birds — when they were called feather 

 guano — but diminishing progressively, sometimes 

 rapidly, in value. However, people still paid a 

 high price for them, especially when one considers 

 that in the meanwhile had appeared on the market 

 (in small quantities, it is true) the Augamos guano 

 which contained close on 19 per cent, nitrogen. 



It is comprehensible that in hot regions with 

 frequent rain nitrogenous organic matter tended to 

 disappear, also the soluble phosphates and a good 

 part of the potash, consequently concentrating the 

 tricalcic phosphates. This was called then phospho- 

 guano. 



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