FERTILITY OF SOILS. 117 



is found in every fertile soil. This mineral may be easily recog- 

 nised, in its crystalline form, in many varieties of rocks. It 

 occurs in this state in the plutonic, volcanic, and metamorphic 

 rocks, although it is usually found only in small quantity. In 

 the plutonic and volcanic rocks it is found in granite (as in the 

 mines of Johann Georgenstadt, Schneeberg, and in the loose 

 gravel near Berlin) ; in syenite it occurs in small crystals, as at 

 Meissen, and in larger crystals at Friedrichswern, in South Nor- 

 way. It exists also in hypersthene, as at Elfdalen, in Sweden, 

 and very often in large quantity, as at Meiches, in the Vogels- 

 berge (a district celebrated for its fertility in wheat), and also in 

 the hills of Lobau, in Saxony ; Tuhlowitz, in Bohemia, &c. 

 It is found in basalt and other volcanic rocks in various localities ; 

 for example, at Wickenstein, at Hamberg, and also at Cabo de 

 Gata, in Spain, and in the volcanic boulders of the Laacher See. 

 Apatite is found also in the metamorphic rocks, and particularly 

 in the talc and chloritic schists ; it occurs in large yellow crys- 

 tals in the micaceous schists of Snarum, in Norway ; and in the 

 calcareous deposits of Pargas, in Finland, and in the Lake Baikal ; 

 in the deposits of magnetic iron ore in Arendal, and in other 

 places in Sweden and in Norway. It is found also in the 

 oceanic rocks, particularly as round fragments and grains in the 

 chalk of Cape la Heve, at Havre, and of the Capes Blancnez and 

 Grisnez, at Calais, and in the layers of limestone at Amberg, 

 &c. (Gustavus Rose.) 



The water of the imperial spring at Aix la Chapelle contains, 

 according to Monheim, 0*142 grains of phosphate of soda in 1 lb. ; 

 that of the Quirinus Spring contains the same quantity, and the 

 water of the Rose spring contains 0*133 of the same salt. The 

 water of the fountain of Carlsbad contains 0*0016 grains of phos- 

 phate of lime. (Berzelius.) The Ferdinand's spring contains 

 0*010 phosphate of soda, according to Wolf. The saline springs 

 of Pyrmont contain 0*022 phosphate of potash, 0*075 phosphate 

 of lime, and 0*1249 grains phosphate of alumina. (Krueger.) 

 When we consider that sea-water contains phosphate of lime in 

 such small quantity that its amount cannot be determined in a 

 pound of water, and yet from this quantity all the living animal* 

 in the sea receive the phosphates contained in their bones and flesh, 



