TABLE OF CONTENTS. 



Preface to first edition --.--..-._iji 



Preface to second edition -,-.---.. -Iv 



Preface to third edition ..-.--....vl 



PART FIRST— THEORY. 

 Chapter I. — General description of earths and soils. 



The necessity for distinguisliingeacli, 13. Description of silicious, aluminous and calcareous earths, 13. 

 Guide to the clieniicnl nomenclature of neutral saUs, 14. Reasons for confining the term " calcareous 

 earth'' to carbonate of lime, 14. Magnesia, 16. Soils are formed by mixtures of earths, 16. Inaccu- 

 racy of ordinary definitions of soils, 17. Plan of nomenclature of soils proposed, 18. 



Chapter II. — On the soils and state of agriculture of the tide-water district of 



Virginia. 



General features of the district, and character of its soils, 19. Ridges, 19. Slopes, 20. River banks 

 and alluvial lands, 20. Destructive tillage, 20. Products, 21. Slavery in connexion with the general 

 system of agriculture, 22. 



Chapter IJf. — The different capacities of soils for receiving improvement. 



First principal propositions stated for discussion, 24. Natural fertility defined, 24. Permanency of either 

 fertile or sterile character of different countries, or particuiar soils, 25. Land naturally poor not capa- 

 ble of being enriched by putrescent manures, 26. Opposing opinions and authorities, 26, 27. Evi- 

 dencis in support, 28. The degree of original fertility is the limit of profitable improvement by putres- 

 cent manures, 29. 



Chapter IV. — Effects of the presence of calcareous earth in soils. 



Calcareous earth not found in poor soils, 30. Its presence alw.'^.ys accompanied by great fertility, 30. 

 Exceptions in soils overcharged, 31. Authors have erroneously taught that calcareous soils were ge- 

 neral, 31. Evidences of such opinions, 32, 33. Erroneous as to Virginia, 34. 



Chapter V. — Results of the chemical examination of various soils. 



Different modes of finding calcareous earth in soils, or to show its absence, 35. Davy's pneumatic appa- 

 ratus and its operation described, 36. Proportions of calcareous earth in sundry species of rich soils, 

 37. Calcareous soils fertile, and poor soils not calcareous, 39. Most rich soils, and even lime-stone 

 soils contain no carbonate of lime, 39. 



Chapter VI. — Chemical examination of rich soils containing no carbonate of lime. 



Rich river lands, 40. Lime-stone soils, 40, 41. Soils from Pennsylvania and New York, 41. Prairie 

 soils ot Alabama generally highly calcareous, 42. 



Chapter VII. — Proofs of the existence of acid and neutral soils. 



Lime in some form present in every soil, 44. Acid not considered an ingredient of soil by any writer of 

 authority, and denied by others. 44. Proofs of the existence of acid in soil, 45. Growth of acid plants, 

 46. Nourished best by dead acid plants, 46. By other putrescent manures, 47. Acid poisonous to 

 cultivated plants, 48. Disappearance of carbonate of lime in soils, and their becoming neutral, 48. 

 All wood ashes contain carbonate of lime, 52. The recent discovery of huniic acid in soils, 53. De- 

 ductions, 55. Supposed gradual and natural changes of soils from calcareous to neutral, and next to 

 acid, 55. 



Chapter VIII. — TTie mode of operation by which calcareous earth increases the 

 fertility and productiveness of soils. 



Silicious and aluminous earths have no chemical power to retain putrescent manure, 58. Calcareous 

 earth has such power and how, 59. f-'ertilizing power exerted in neutralizing acid, 61. And in alter, 

 iug the texture and absorbency of soils, 62. 



