340 MANURES. 



According to this analysis one ton (2000 Ibs.) farm-yard 

 manure contains 



Soluble silica (silicic acid) 24 Ibs. 



Ammonia (actual or potential) 15f " 



Phosphate of lime 13^ " 



Lime 23 T V " 



Magnesia 3^ " 



Potash 13J " 



Soda If " 



Common salt & " 



Sulphuric acid 2J- " 



Water 1323f " 



Woody fibre, &c 579 " 



Of course no two samples of farm-yard manure are ex- 

 actly of the same composition. That analyzed by Dr. 

 Yoelcker was selected with much care, as representing a 

 fair average. 



GREEN SAND MARL (OF NEW JERSEY). 



Protoxide of iron 15.5 



Alumina 6.9 



Lime 5.3 



Magnesia 1.6 



Potash 4.8 



Soluble silica 32.4 



Insoluble silica and sand 19.8 



Sulphuric acid -6 



Phosphoric acid 



Water 8.0 



Carbonic acid, &c 3.8 



100.0 



