FERTILIZERS. 47 



that some of that imported into this country from England 

 has been found to be grossly adulterated. All that we 

 farmers can do is, to buy it under a warrant that it contains 

 given quantities of nitrogen, phosphoric acid, and potash. 

 Mr. Chapman says in his letter, that, in bringing the nitro- 

 gen up to that required for Standard, sulphate of am- 

 monia was used. Assuming this to be so, and that it is 

 not obtained from any organic source, then it would be of 

 the same value as though obtained from the guano itself. 

 From tests I made on grass-land, I found that the Peru- 

 vian guano I purchased of Messrs. Chapman & Co. started 

 the grass earlier than did an equal value of sulphate of 

 ammonia applied at the same time, side by side, on an 

 equal area. This satisfied me that its nitrogen was not 

 derived wholly, if at all, from waste fish or meat. 



Ten years ago the New York Agricultural Society took 

 up the matter of the adulteration of Peruvian guano, 

 purchased eleven bags of as many dealers, and had them 

 analyzed. The result was a value differing from $38.33 to 

 $107.68, though each was sold at the same price per ton. 

 In the report of the Connecticut agricultural station for 

 1881, it is stated, that, while Peruvian guano used formerly 

 to contain no more than one or two per cent each of soda, 

 sulphuric acid, and chlorine, the sample analyzed that 

 year contained about thirteen per cent of sulphate of soda 

 (salt-cake), and eleven per cent of common salt. 



The Chincha Islands, which have been the great source, 

 in past years, of Peruvian guano, lie near the coast of 

 Peru, barren granite rocks, with great depth of water 

 close by them, so that in places the largest vessels can 

 lay alongside and be loaded from the land by a shoot 

 entering into their holds. The guano, a thoroughly rotted 

 mass of bird-dung, in which are mixed feathers, carcasses, 

 and eggs, was from four to a hundred feet in depth. 



