FERTILIZERS. 



277 



The present extent of this industry and the 

 use made of fish-manures may be gathered from 

 the fact that, in 1875, the nitrogen derived 

 from fish-manures was equal to that contained 

 in 30,000 tons of Peruvian guano. In 1880 

 there were 79 fish-factories on the Atlantic 

 coast, employing 448 vessels and 3,200 men; 

 2,035,000 gallons offish-oil were produced, and 

 45,000 tons of scrap. The various kinds of ani- 

 mal refuse, dried blood, tankings, fish-scrap, 

 etc., are used chiefly for " ammoniating " super- 

 phosphates. 



Peruvian Guano. This wonderful material, 

 whose use by millions of tons has done so 

 much to restore fertility to the depleted soils 

 of Europe and America, has been in the past 

 the most important of the various commercial 

 fertilizing materials. Peruvian guano, as is 

 well known, consists mainly of the excrement 

 of birds, which has been accumulating for cen- 

 turies on the almost rainless coasts and adja- 

 cent islands of Peru and Chili. What makes 

 the excrement of birds particularly valuable as 

 a fertilizer is that the excretion of both kidney 

 and intestines is mixed in the cloaca, and 

 voided in a comparatively solid condition. 

 "What makes guano so far superior to any 

 fresh manure of the kind is that the sole diet 

 of these birds was fish, which are rich in phos- 

 phoric acid and nitrogen, and also that all the 

 moisture was speedily taken out of the mass 

 by the dry, hot winds continually passing over 

 it. It is interesting to note that our lands are 

 continually suffering a loss in nitrogen and 

 other elements of plant-food which, through 

 various channels, finds its way continually to 

 the ocean and passes out of our reach; and 

 that through the agency of these birds many 

 million tons of these same elements have been 

 recovered from the ocean, and stored up where 

 of all places they would keep best for our use, 

 long before we felt the loss and desired its re- 

 placement. The use of guano as a fertilizer 

 dates back at least to the time of the Incas in 

 the twelfth century. The old Peruvians had 

 a proverb to this effect : 

 " Guano can work miracles, 



Though it is not numbered with the saints." 

 Ilumboldt brought samples to Europe, the 

 analyses of which were published in 1806. 

 A more complete investigation was made by 

 Liebig and Wohler in 1837. In 1840 a ship- 

 load was brought to England, and since then 

 many million tons have been taken to Europe 

 and to this country. Of late the supplies of 

 Peruvian guano have been curtailed and unre- 

 liable, partly because of the exhaustion of some 

 of the deposits, and partly because of the mis- 

 government and war in Peru. The future of 

 the Peruvian guano supply it is impossible to 

 forecast. The supply for the coming year is 

 said to be assured, and it is the opinion of 

 those in position to judge, that, with a stable 

 and enlightened government, Peru may supply 

 Europe and America with guano for years to 

 come. 



Phosphatic Guanos and EocTc Phosphates. 

 Peruvian guano being little exposed to rain, 

 has retained a large portion of its soluble 

 constituents. Many of the bird deposits, how- 

 ever, are subject to more or less frequent 

 rains, which either wash back into the ocean 

 the freely soluble materials, or bring them 

 into reaction with the coral limestone by 

 which they are in part retained. As a rule, 

 the nitrogen and potash are lost, while the 

 phosphates are retained and become a valuable 

 source of phosphoric acid, forming what are 

 called the phosphatic guanos. In former 

 years we received a great deal of this mate- 

 rial from some small Pacific islands of coral 

 formation under the name of American guano. 

 In 1856 the United States assumed the protec- 

 tion of all the guano islands in the Pacific 

 Avhich lay within 10 of the equator north and 

 south, and between longitude 150 and 180. 

 The islands chiefly worked were Baker's, How- 

 land's, and Jarvis's. The guano was brown, 

 pulverulent, and coarse-grained, and could be 

 shoveled without picks. It contained from 

 thirty to forty per cent of phosphoric acid, and 

 by treatment with sulphuric acid made excel- 

 lent superphosphates. For some time past, 

 however, the whole product has been carried 

 to Europe. Our main supply of this material 

 comes now from the West Indies. Just at the 

 mouth of the Gulf of Venezuela, in the Car- 

 ibbean Sea, lie Great Curacoa and Little Cu- 

 racoa Islands. For some years they have fur- 

 nished large quantities of guano to Germany 

 and the United States. The Little Curacoa 

 guano from which most of our supply comes 

 is poorer in phosphoric acid than the other, 

 averaging from twenty-five to twenty-eight 

 per cent. Its mechanical condition, however, 

 is better. Great Curacoa guano goes largely 

 to Germany. It is hard and rocky, but has 

 from thirty-eight to forty-two per cent of 

 phosphoric acid. Another phosphatic guano, 

 which has been used to considerable extent in 

 this country, is the Orchilla, which has a some- 

 what similar composition, though it is of rather 

 inferior value and importance. Another rock 

 phosphate from the West Indies, the Navassa, 

 is now extensively used in this country as ma- 

 terial for the superphosphate manufacture. 

 The phosphatic deposits of Navassa Island were 

 formed under water and thrown up by vol- 

 canic action. The phosphate is inferior to the 

 phosphatic guano mentioned, especially be- 

 cause of a large content of iron and alumina, 

 which causes superphosphates made from it to 

 " revert " badly. 



South Carolina Phosphates. Dr. Jenkins, in 

 the article already referred to, speaks of this as 

 follows : " The South Carolina phosphate beds I 

 believe are, and for some time will be, the chief 

 source of raw material for our domestic super- 

 phosphate manufacture. 



"For most of the facts given in this connec- 

 tion I am indebted to an interesting printed 

 report by Professor C. U. Shepard, Jr., of 



