GOLDSMITH COMPANY'S SOIL CHEMIST, ROTHAMSTED EXPERIMENTAL STATION

Cambridge: at the University Press 1911

PREFACE

CONTENTS

LIST OF ILLUSTRATIONS

INTRODUCTION

CHAPTER I

WHAT IS THE SOIL MADE OF?

Fig. 1. Soil and subsoil in St George's school garden

Fig. 2. Columns showing what 100 parts of soil and subsoil were made of

Fig. 3. Columns showing what 100 parts of dried soil and subsoil were made of

CHAPTER II

MORE ABOUT THE CLAY

Fig. 4. Clay was plastered over a square piece of board and completely covered it. After drying for a week the clay had shrunk and cracked

Fig. 5. Clay swelling up when placed in water and overflowing from the egg-cup into which it was put

Fig. 6. Landslip in the Isle of Wight

Fig. 7. A thin layer of clay a entirely prevents the water running through

Fig. 8. Sand allows air to pass through it, and so water runs out of the bottle. Clay does not let air pass, and the water is therefore kept in, even though the tube is open.

Fig. 9. A brick standing in water. The air in the brick is driven inwards by the water and forces the liquid up the tube in order to escape

CHAPTER III

WHAT LIME DOES TO CLAY

Fig. 10. Addition of lime to turbid clay water now makes the clay settle and leaves the water quite clear

CHAPTER IV

SOME EXPERIMENTS WITH THE SAND

Fig. 11. Sand dunes, Penhale sands, Cornwall

Fig. 12. Sand from Penhale sand dunes blowing on to and covering up meadows

Fig. 13. Model spring. A box with glass front contains a layer of clay and one of sand. Water that falls on the sand runs right down to the clay but can get no further, and therefore flows out through the tube c at the junction of the clay and the sand. The same result is obtained when chalk takes the place of sand

Fig. 14. Foot of a chalk hill at Harpenden where a spring breaks out just under the bush at the right-hand side of the gate

Fig. 15. "The little pool below the tree"

Fig. 16. Water bursting out from an underground spring, Old Cateriag Quarry, Dunbar

Fig. 17. Two positions of sand. A is dry because the water can drain away and break out as a spring at c. B is wet because the water cannot drain away

Fig. 18. The roads round Wye. As far as possible they keep off the clay (the plain part of the map) and keep on the chalk or the sand (the dotted part of the map)

CHAPTER V

THE PART THAT BURNS AWAY

Fig. 19. Cutting and carrying peat for fuel, Hoy, Orkney

CHAPTER VI

THE PLANT FOOD IN THE SOIL

Fig. 20. Rye growing in surface soil (Pot 3), subsoil (Pot 4), and sand (Pot 5)

Fig. 21. Mustard growing in surface soil (Pot 3), subsoil (Pot 4), sand (Pot 5)

Fig. 22. Mustard growing in surface soil previously cropped with rye (Pot 1) and in surface soil previously uncropped (Pot 2)

Fig. 23. Pieces of grass, leaves, etc. change into plant food in the surface but not to any great extent in the subsoil. Mustard is growing in surface soil (Pot 3), in surface soil and pieces of grass (Pot 6), in subsoil (Pot 4), and in subsoil and grass (Pot 7)

CHAPTER VII

THE DWELLERS IN THE SOIL

Fig. 24. Soil in which earthworms have been living and making burrows

Fig. 25. Fresh soil turns milk bad, but baked soil does not

Fig. 26. Soils contain tiny things that grow on gelatine

Fig. 27. Bottle containing lime water, used to show that breath makes lime water milky

Fig. 28. A bag of soil is fixed into a flask containing lime water. In a few days some of the air has been used up, and the lime water has turned milky

CHAPTER VIII

THE SOIL AND THE PLANT

Fig. 29. Loam and sand both retain water, but loam better than sand

Fig. 30. Water can rise upwards in soil. It can, in fact, travel in any direction, from wet to dry places

Fig. 31. Wheat growing in soils supplied from below with water. All the water the plant gets has to travel upwards

Fig. 32. Mustard growing in soils supplied with varying quantities of water. 16 very little water, 3 a nice amount of water, 15 too much water

Fig. 33. This wheat growing on very moist soil was still green and growing vigorously, whilst this wheat growing on rather dry soil was yellow and ripe

Fig. 34 a. Plants collected on dry sandy soil. Broom, sheep's fescue, crested dogstail and gorse, all with narrow leaves

Fig. 34 b. Plants collected on moist loam. All have wide leaves

Fig. 35. Plants give out water through their leaves

Fig. 36. Stephen Hales's Experiment (from Vegetable Staticks, Vol. I. 1727)

Fig. 37. Hill slope near Harpenden. Woodland at the top, arable land lower down. In the valley there is grass land but this is hidden by the cottages

Fig. 38. View further along the valley, woodland and arable above rough grass land near the river

Fig. 39. Rough grass pasture near the river, above that is arable land and still higher is woodland

CHAPTER IX

CULTIVATION AND TILLAGE

Fig. 40. After harvest the farmer breaks up his land with a plough and then leaves it alone until seed time

Fig. 41. Rolling in mangold seeds on the farm

Fig. 42. Soil sampler. (See p. 82 for description)

Fig. 43. Cultivation and mulching reduce the loss of water from soils

Fig. 44 a. The hoed plot, no weeds. Maize cannot compete successfully against weeds

Fig. 44 b. Untouched plot, many weeds

Fig. 45. A plot of wheat left untouched since 1882 at Rothamsted has now become a dense thicket

Fig. 46. A wheat field in May. The large patch in the centre where the crop is doing badly lay under water for much of the winter because of the bad drainage

CHAPTER X

THE SOIL AND THE COUNTRYSIDE

Fig. 47. Highly cultivated sand in Kent. Gooseberries are growing in the foreground, vegetables behind, and hops in background

Fig. 48. A Surrey heath

Fig. 49. Woodland and heather on light sandy soil, Wimbledon Common

Fig. 50. Poor sandy soil in Surrey, partly cultivated but mainly wood and waste

Fig. 51. Open chalk cultivated country, Isle of Thanet

CHAPTER XI

HOW SOIL HAS BEEN MADE

Fig. 52. Cliffs at the seaside, Manorbier, Pembrokeshire

Fig. 53. Inland cliff. Salisbury Crags, Arthur's Seat, Edinburgh

Fig. 54. Model of a stream. In A, where the stream flows quickly, the water is clear and the sediment free from mud. In B, where it flows slowly, the water is turbid and the sediment muddy

Fig. 56. The two sides of the river at the bend

Fig. 56. The winding river Stour. The river winds from the right to the left of the picture, then back again, and then once more to the left, passing under the white bridge and in front of the barn.

Fig 57. Sketch map showing why Godmersham and Wye arose where they did on the Stour. At A, the gravel patch, the river has a hard bed and can be forded. A village therefore grew up here. At B, the clay part, the river has a soft bed and cannot be forded. The land is wet in winter, and the banks of the stream may be washed away. It is therefore not a good site for a village

Fig. 58. Ford and Coldharbour, near Harpenden

APPENDIX

INDEX