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 Nature of changes undergone by food in process of digestion 235 Litter-- Its uses 236 Straw as litter, and its qualifications 237 Composition of different kinds of straw 238 Loam as litter 239 Peat as litter 240 Comparison of properties of peat-moss and straw 241 The bracken-fern as litter 241 Dried leaves as litter 242 Manures produced by the different animals-- Horse-manure-- Amount produced 243 Its nature and composition 243 Amount of straw used for litter 244 Sources of loss on keeping 245 How to prevent loss 245 Use of "fixers," and the nature of their action 245 Cow-manure-- Amount produced 248 Its nature and composition 248 Amount of straw used as litter 248 Sources of loss on keeping 249 Advantages of short dung 249 Pig-manure-- Amount produced 250 Its nature and composition 250 Amount of straw used as litter 251 Sheep-manure-- Amount produced 251 Nature and composition 251 Amount of straw used as litter 252 Methods of calculating amount of manure produced on the farm 252, note Fermentation of farmyard manure-- Action of micro-organic life in producing fermentation 255 Two classes of bacteria active in this work, aerobies and anaerobies 255 Conditions influencing fermentation-- Temperature 256 Openness to the air 256 Dampness 257 Composition of manure 257 Products of fermentation 257 Analyses of farmyard manure-- Dr Voelcker's experiments 259 Variation in composition 259 Amounts of moisture, organic matter (containing nitrogen), and mineral matter 260 Its manurial value compared with nitrate of soda, sulphate of ammonia, and superphosphate 260 Comparison of fresh and rotten manure-- The nature and amount of loss sustained in the process of rotting 261 Ought manure to be applied fresh or rotten? 262 Relative merits of covered and uncovered manure-heaps 263 Methods of application of farmyard manure to the field-- Merits and demerits of the different methods 265 Setting it out in heaps 265 Spreading it broadcast, and letting it lie 266 Ploughing it in immediately 267 Value and function of farmyard manure-- As a supplier of the necessary elements of plant-food 268 As a "universal" manure 269 Proportion in which nitrogen, phosphoric acid, and potash are required by crops 269 Proportion in which they are present in farmyard manure 270 Farmyard manure poor in nitrogen 270 Lawes' and Gilbert's experiments 271 How it may be best reinforced by the use of "artificials" 271 Indirect value of farmyard manure as a supplier of humus to the soil 273 Its influence on soil-texture 273 Its influence in setting free inert fertilising matter in the soil 274 Rate at which farmyard manure ought to be applied 275 Lasting nature of farmyard manure 276 Its economic value 276

APPENDIX TO CHAPTER VII. NOTE I. Difference in amount of excreta voided for food consumed 279 II. Solid excreta voided by sheep, oxen, and cows 279 III. Urine voided by sheep, oxen, and cows 280 IV. Percentage of food voided in the solid and liquid excrements 281 V. Pig excrements 281 VI. Manurial constituents in 1000 parts of ordinary foods 282 VII. Analyses of stable-manure, made respectively with peat-moss litter and wheat-straw 283 VIII. Analyses of bracken 283 IX. Analyses of horse-manure 283 X. The nature of the chemical reactions of ammonia "fixers" 284 XI. Analyses of cow-manure 286 XII. Composition of fresh and rotten farmyard manure 286 XIII. Comparison of fresh and rotten manure 288 XIV. Lord Kinnaird's experiments 289 XV. Drainings of manure-heaps 290 XVI. Amounts of potash and phosphoric acid removed by rotation from a Prussian morgen (.631 acre) 290 XVII. Composition of farmyard manure (fresh) 291 XVIII. The urine (quantity voided) 291