PEINCIPAL PHOSPHATE DEPOSITS. 49 



Distribution of Phosj^liates in the Different Geological Forma- 

 tions. — On examining the subject from a geological point of view, 

 phosphoric acid, or phosphoric acid and nitrogen, is found in the 

 following formations : — 



1. Gneiss Epoch, as apatite in Sweden, in Finland, in Norway, 

 in the mountains of the east coast ol North and South America. 



II. PalcBOzoic {or Primary) Epoch. — 1. Silurian Formation. — 

 x\s phosphorites in Spain and in the south of Eussia. 2. De- 

 vonian Formation. — As phosphorites in Germany. 3. Carhonifer- 

 OILS Formation. — As Blackband in Great Britain and Germany. 



III. Mesozoic or Secondary EjJOcJi. — 1. Trias Formation. — As 

 Bone Bed and fossil bones in England, Germany, and Switzerland. 

 2. Jurassic Formation. — As coprolites in Germany and England. 

 (Lias.) — As phosphatic nodules in France and Germany. (Osteo- 

 lithes.) — As phosphorite in French Jurassic marls. 3. Cretaceous 

 Formation. — As coprolites in France, in England, in Germany, and 

 in Holland. As phosphorite in Spain, in Belgium, in France, in 

 Austria-Hungary and in Eussia. 



Cainozoic or Tertiary Ejjoch. — Eocene Formation. — As copro- 

 lites in England and Germany. As phosphates in France, Algeria, 

 Tunis, the Carolinas, Tennessee and Florida. 



Quaternary and Becent Epoch.— 1. As fossil hones. 



2. As phosphate in the islands of Navassa, Eedonda, Eata, St. 

 Martin, Curacao, Testigos, Buenos Aires. 



3. As guano crusts in the islands of Starbuck, Flint, Sombrero, 

 Avalo, Los Eoques. As phospho guano in the islands of Baker, 

 Howland, Fanning, Jarvis, Maiden, Mary, Enderbury, Phoenix, 

 Sydney, Vivorilla, Mona, George, Eaza, Clipperton, Monk's at 

 Mejillones, in the islands of Leysan, French, Frigatte Shoal, at 

 Bramble Cays, Shoal Bay, Shark's Bay, in the islands of Timor, 

 Ashmore, Brown, Jones, Lacepede, Abrolhos, Huon, Birds, Kurian 

 Murian, Swan, and at Algoa Bay. 



4. As guano in Peru, Chili, Patagonia. In the islands of 

 Galapagos, Bat, Ishaboe, Damaraland, and Saldanha Bay. 



5. Bat guano on the Mediterranean coasts, Egypt, Sardinia, 

 Galicia, Porto Eico. 



It will be convenient to add to this classification, the substances, 

 manufactured by industry, such as bone black (spent char), bone 

 ash, artificial guano manufactured from the excrements and the 

 dead bodies of animals, fishes, lobsters ; in addition to the precipi- 

 tated phosphate of glue and gelatine factories, and finally the 

 phosphates of basic slag. The following table prepared by Dr. M. 

 Ullmann contains the analyses of all phosphates known up to the 

 present time. x\s this document is absolutely unique in scientific 

 literature it is given here at the risk even of repeating what has 

 been said previously. 



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