( 805=555 ) 
CONTENTS. 
INTRODUCTION. 
Influence of Scientific Researches — Discriminatiovi between Theoretical Specu- 
lations and Scientific Facts — Value of Kothamsted Field Experiments 
Pages 541-542 
CHATTER I.— The Soil 
Use of a knowledge of the Chemical Composition of the Soil — Analyses do not 
always show its Agricultural capabilities^ — Absorbent Power of Soils — 
Variableness of their retentive Powers — Absorption of Ammonia — Effect of 
Pain on Top-dressings of Ammoniacal Manures — Best time to apply Arti- 
ficials — Use of Lime and Marl — Value of Lime in poor sandy Soils — 
Influence of Lime upon Manures containing Soluble Phosphates — Beneficial 
results of Bone-dust to Root Crops on Light Land — Closer approach of 
Practice and Science, in consequence of wider diffusion of Chemical 
Knowledge — Questions often answered by the Analyses of Soils — Influence 
of Experiments on Modern Cultivation — Permanent fertility raised by 
<:onstant Manurings .. .. .. .. .. Pages 542-550 
CHAPTER II.— Coniinuous Cropping. 
Experiments on Continuous' Cropping — Tabular Statement of Results — Efi'ect 
of difl"erent Manures — Modifications in Cropping by using Artificials — Con- 
tinuous Corn-growing by Mr. Prout — Composition of the Soils of his Farm 
— Cost of his Farm — Steam Cultivation — Annual Expenditure — How Arti- 
ficial ilanures are applied — Results of sales of Crops — Corn Crops grown — 
Pie turn per Acre — Land improved in Value .. Pages 550-556 
CHAPTER III.— Manures. 
Improvements in Land Cultivation — Powers of Nitrogen — Sources of Nitrogen 
in Vegetation from the Atmosphere — Non-ability of Plants to assimilate 
free Nitrogen from the Air — Proportion of Nitrogen unrecoverable— Carried 
away by Drainage — Results of investigation into composition of Waters of 
Land-drainage— Farmyard Manure when best applied — Artificials — Nitrate 
of Soda only retained in Land one Season — Increase in the use of Artificials 
—Magnitude of the English Manufacture— Raw Materials used— Phosphatic 
Materials— Nitrogenous Manures — Saline Alkaline Materials — Uses of 
Manures for Corn— For Roots— Disposal of Town Sewage- Effect of Soil 
