CONTENTS x"> 



Superphosphate— Fate of Superphosphate applied to '*"■ 

 the Soil -Soils appropratc to Hasic Slag — Neutral 

 rhosphatic Manures for Light Soils— Comparison of 

 Bone Meal with other I'hosphatic Fertilisers • '3'^ 



CHAPTER VI 



THE POTASSIC FKRTIUSERS 



Early Use of Wood Ashes- The Stassfurt Deposits Manu- 

 facture and Composition of Commercial Potash Y crtilisen> 

 —The Retention of Potash by the Soil- The Function 

 of Potash in the Nutrition of the Plant -ncpendcnce of 

 Carbohydrate Formation upon Potash, as illustrated in 

 the Uarlcy and Mangold Crops— The Action of Nitrate 

 of Soda upon Insoluble Potash Compounds in the Soil — 

 Potash Fertilisers as promoting the Growth of Legu- 

 minous Plants — KtTects of Potash Star%ation upon 

 Vegetation— Potash as a Preventive of Fungoid Disease 

 — Potash as prolonging the Cirowth of the Plant- 

 Destruction of the Tilth of Clay Soils by Potash Salts- 

 Soils deficient in Potaih . .138 



CHAPTER VII 

 FARMYARD MANURE 



Variable Composition of Farmyard Manure— The Fate of the 

 Constituents of Food during Digestion and Kxcrction— 

 Composition of Urine and F.xccs of Farm Animals- 

 Fermentation Changes taking place during the Making 

 of Dung— The Breakdown of the Nitrogenous Hodics 

 and of the Carbohydrates— Gases found in the Dunghill 



— Losses of Nitrogen during the making of Farmyard 

 Manure— Preservatives used to minimise the Losses 

 during Dung-making— Composition of Farmyard Manure 



— cAe-fed V. Ordinary Manure— Long and Short 

 Manure— London Dung— The Value of Fresh Manure— 

 The F"ertilising Value of Farmyard Manure— Recovery 

 of its Nitrogen in the Crop— Long Duration of the Action 

 of Farmyard Manure— Farmyard Manure as a Carrier 

 of Weeds or Disease— The Physical Effects of Farmyard 

 Manure upon the Soil— The Improvement in Texture 

 and Water-retaining Power— Value of Farmyard Manure 

 as a Mulch on Grass Land — Farmyard Manure best 

 utilised for the Root Crop or Grass Land— \'alue of 

 Farmyard Manure : Cost of making One Ton . .178 



