XV111 CONTENTS. 



Felspar and other potash minerals 213 



Stassfurt salts . . . . . . . . .214 



Occurrence of saltpetre 215 



Occurrence of potash in the soil . . . . . .215 



Potash chiefly in insoluble condition in soils . . . .216 



Percentage of potash in plants and plant-ash . . . .216 



Occurrence of potash in animal tissue . . . . .217 



Sources of loss of potash 217 



Amount of potash removed in crops . . . . .218 



Amount of potash removed in milk . . . . . .218 



Potash manures ....... .218 



APPENDIX TO CHAPTER VI. 

 NOTE 



I. Amount of potash in different minerals .... 220 

 II. Quantity of potash obtained from 1000 Ib. of different 



kinds of vegetation in the manufacture of potashes . 220 



PART III. MANURES. 



CHAPTER VII. FARMYARD MANURE. 



Variation in its composition ....... 223 



Made up of three classes of constituents ..... 224 



Solid excreta 



Its nature 224 



Difference in composition of the solid excreta of the 

 different farm animals ...... 224 



Causes of this difference ...... 225 



Percentage of manurial ingredients in solid excreta of 

 different animals . . . . . . .226 



Urine 



Its nature 228 



Variation in its composition 229 



Causes of this variation ....... 229 



Manurial value of the urine of the different farm animals 230 

 Percentage of the organic matter, nitrogen, and mineral 

 substances in the food, voided in the solid excreta and 



urine 232 



Comparison of manurial value of total excrements of the 

 different farm animals ...... 234 



