17 



France also possesses some deposits of this character at Bellegarde, 

 near the Swiss frontier, and also at Montpellier and Avignon, yielding 

 54% tribasic phosphate of lime. 



NODULAR, CONCRETIONARY AND ARKNACEOUS PHOSPHATES. 



These by far the most important of nature's phosphatic reserves, 

 comprising as they do, the South Carolina deposits, the French deposits 

 of the Somme, Ardennes and Meuse, the Belgian fields of Mons and 

 those more lately opened up at Liege (Hesbaye). The so-called "Bor- 

 deaux Phosphates," because being formerly shipped from that port, but 

 having their leal origin in the region of Quercy, comprising portions of 

 the departments of the Lot, Tarn and Garonne and Aveyron, also fur- 

 nish a considerable quantity of nodular or phosphatic concretions of 

 kidney shape of great purity (88%), and curious geological interest. 

 These are well represented by specimens on the table, and coming 

 from the crevices in the Oolitic limestones, accompanied by debris of 

 Tertiary age (Eocene), the walls of the crevices or fissures being at the 

 same time incrusted with phosphorite of a high degree of purity attain- 

 ing 8o% of tribasic phosphate of lime. 



We must not omit here the Florida nodular beds of land and river 

 formation, which are now enjoying such a glorious boom. 



As a peculiarity of this Bordeaux phosphorite, we may mention 

 that it contains a very appreciable proportion of iodine. 



The Russian deposits, situated between the Rivers Desna and Don, 

 occur in the Cretaceous system, at about the same horizon as the Cam- 

 bridgeshire coprolites and may be described as nodular. 



The Nassau or Lahn concretions in clay are of Tertiary age, and 

 although not exhibiting signs of organic remains are generally believed 

 to be of animal origin, they attain 6o to 75% phosphate of lime, but 

 too ferruginous to be much in request for superphosphate manufacture. 



The Belgian (Ciply) deposits, which have furnished over 150,000 

 tons per annum of a 40 to 50% product, are of a nodular character,, 

 although the grains are often so fine as to be considered more 

 correctly arenaceous. 



The same may be said of the very remarkable French deposits, 

 discovered near Amiens in 1886, and known as the Somme phosphates. 



