Manures and the principles of manuring

Farmyard manure is the oldest, and is still undoubtedly the most popular, of all manures. It has stood the test of long experience, and has proved its position as one of the mos...

Reference has been so repeatedly made in the preceding pages to the Rothamsted experiments on manures, that it may form a fitting conclusion to the present treatise to give a sh...

Agricultural Chemistry, like most branches of natural science, may be said to be entirely of modern growth. While it is true we have many old speculations on the subject, they c...

Of manurial ingredients, nitrogen is by far the most important, and on the presence and character of the nitrogen it contains, the fertility of a soil may be said to be most lar...

The question, What constitutes fertility in a soil? is by no means an easy one to answer. If we say, The presence of a plentiful supply of the constituents which form the plant'...

The most important compound of nitrogen for the plant is _nitric acid_. It is as nitrates that most plants absorb the nitrogen they require to build up their tissue. In nature t...

In the consideration of _artificial_ manures, guano deserves the first place. This it does mainly on historical grounds, as it is now largely a manure of the past. Not merely ha...

In this chapter we shall attempt to summarise briefly the results of experiments on the manuring of some of the commoner crops, and we shall start with the manuring of cereals.

The value of a manure to the farmer depends on the proportion of _nitrogen_, _phosphoric acid_, and _potash_ it contains, as well as--and this is hardly less important--the cond...

Nitrate of soda,[202] or, as it is more correctly designated from a chemical point of view, sodium nitrate, now forms the chief artificial nitrogenous manure in use. Along with...

The conditions which regulate the application of manures are many and varied, and the subject, it must be admitted, despite the large amount of investigation already carried out...

As was mentioned in the chapter on Bones, Liebig in the year 1840 discovered that the effect of adding oil of vitriol, or sulphuric acid, to bones was to render the phosphate th...

In this substance we have a most important addition to our phosphatic manures. It has been in the market since 1886, and the consumption alone in Germany in 1887 amounted to nea...

We now come to discuss those manures which we may class under the term _Indirect_, because their value is due, not to their direct action as suppliers of plant-food--like those...

A most important manure, and one to the history of which very peculiar interest attaches, is Bones. Employed first in 1774, their use has steadily increased ever since, and thei...

In the previous chapter mention was made of gypsum as a compound of lime, but no reference to its action as a manure was made. In the past, gypsum was used extensively and highl...

The value of sewage as a manure has been in the past enormously overrated, and much misunderstanding has existed on the part of the public on the question of the profitableness...

We now come to consider the position of phosphoric acid in agriculture. The question is, however, very much simpler in its nature than that of nitrogen, and may be consequently...

In this chapter we shall give an account of the more commonly occurring mineral phosphates. In Chapter V., where we discussed the position of phosphoric acid in agriculture, it...

Having considered the manuring of the different crops, we may now pass on to the consideration of some points in the method of application and on the mixing of manures.

We may, lastly, consider the position of _potash_ in agriculture, the only ash ingredient of the plant, in addition to phosphoric acid, which it is as a rule necessary to add as...

The value of ammonia salts as a manure has been long recognised; indeed till recently ammonia was thought to be the most valuable form in which nitrogen could be applied as a pl...

In Chapter VI. we pointed out that of the three manurial ingredients potash was the one most abundantly occurring, and that, consequently, the necessity of adding it in the form...

In addition to the manures which have been discussed in previous chapters, there are a number of minor manures which are used to a very much smaller extent--dried blood, hoofs,...

Let us, in the first place, clearly understand what we mean by a manure. The word manure comes from the French word _manoeuvrer_, which simply means "to work with the hand," hen...

The use of composts is an old one. Before artificial manures were so plentiful as they are at present, much attention was paid by farmers to their preparation. A compost is gene...

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 fa...

The adoption of irrigation as a means of utilising sewage, suggests a short consideration of the value of liquid manures. It has been a custom on many farms to apply the liquid...

The Rothamsted experiments and the nitrogen question 115 Different forms in which nitrogen exists in nature 116 Relation of "free" nitrogen to the plant 117 Combined nitrogen in...

Process of nitrification 161 Occurrence of nitrates in the soil 162 Nitre soils of India 162 Saltpetre plantations 163 Cause of nitrification 165 Ferments effecting nitrificatio...

What constitutes fertility in a soil 65 I. Physical properties of a soil 66 Kinds of soils 67 Absorptive power for water of soils 67 Absorptive power for water of sand, clay, an...

PAGE Beginning of agricultural chemistry 4 Early theories regarding plant-growth 4 Van Helmont 4 Digby 6 Duhamel and Stephen Hales 8 Jethro Tull 9 Charles Bonnet's discovery of...

Cereals 493 Especially benefited by nitrogenous manures 494 Power of absorbing silicates 494 Barley 495 Period of growth 495 Most suitable soil 496 Farmyard manure not suitable...

Importance in agriculture 293 Influence on British farming 294 Influence of guano not wholly good 295 Value of guano as a manure 296 Origin and occurrence of guano 297 Variation...

Amount of exports 332 Date of discovery of nitrate deposits 333 The origin of nitrate deposits 334 Forbes and Darwin on the theory of their origin 335 Source of nitric acid in n...

Value of chemical analysis 539 Interpretation of chemical analysis 539 Nitrogen 540 Phosphoric acid 541 Importance of mechanical condition of phosphate 542 Potash 542 Other item...

Nature of experiments on crops and manures 561 Soil of Rothamsted 561 Table I. List of Rothamsted field experiments 562 Wheat experiments-- Unmanured plots 562 Wheat grown conti...

Occurrence of phosphoric acid in nature 199 Mineral sources of phosphoric acid 200 Apatite and phosphorite 200 Coprolites 201 Occurrence of phosphoric acid in guanos 202 Univers...

Influence of manures in increasing soil-fertility 474 Influence of farmyard manure on the soil 475 Farmyard manure _v._ artificials 476 Farmyard manure not favourable to certain...

Discovery of superphosphate by Liebig 382 Manufacture of superphosphate 383 Nature of the reaction taking place 385 Phosphates of lime 385 Reverted phosphate 389 Value of revert...

Potash of less importance than phosphoric acid 212 Occurrence of potash 213 Felspar and other potash minerals 213 Stassfurt salts 214 Occurrence of saltpetre 215 Occurrence of p...

Lime 449 Antiquity of lime as a manure 449 Action of lime 449 Lime a necessary plant-food 450 Lime of abundant occurrence 452 Lime returned to the soil in ordinary agricultural...

Early use of bones 359 Different forms in which bones are used 360 Composition of bones 362 The organic matter of bones 363 The inorganic matter of bones 363 Treatment of bones...

Gypsum 462 Mode in which gypsum acts 462 Salt 465 Antiquity of the use of salt 465 Nature of its action 465 Salt not a necessary plant-food 466 Can soda replace potash? 466 Salt...

Its manufacture 401 Not at first used 403 Discovery of its value as a manure 403 Composition of basic slag 404 Processes for preparing slag 406 Solubility of basic slag 408 Darm...

Coprolites 373 Canadian apatite or phosphorite 374 Estremadura or Spanish phosphates 375 Norwegian apatite 376 Charlestown or South Carolina phosphate 376 Belgian phosphate 377...

Value of ammonia as a manure 352 Sources of sulphate of ammonia 353 Ammonia from gas-works 353 Other sources 354 Composition, &c., of sulphate of ammonia 355 Application of sulp...

Relative importance 418 Scottish soils supplied with potash 419 Sources of potassic manures 419 Stassfurt potash salts 420 Relative merits of sulphate and muriate of potash 421...

Equal distribution of manures 531 Mixing manures 532 Risks of loss in mixtures 533 Loss of ammonia 533 Effects of lime on ammonia 535 Loss of nitric acid 536 Reversion of phosph...