ACTION OF THE SOIL ON PLANTS. 159 



Emily But supposing the soil to consist of two lay- 

 ers, the one of sand, the other of clay, the plough should, 

 I suppose, go deep enough to mix them together. 



Mrs. B. No doubt their union produces as excellent 

 a soil as their separation makes a bad one. It signifies 

 not which is uppermost before ploughing ; the more they 

 are mixed and incorporated together the better. 



Caroline. But supposing there should be a good, rich, 

 vegetable soil on the surface, and layers of sterile ground 

 beneath ? 



Mrs. B. Then a light plough should be used, and as 

 much care taken to prevent the mixture of the two, as to 

 effect it in the former case ; in short, attention must al- 

 ways be paid to the nature and locality of the soil. 

 Ploughing must vary, also, according to the nature of the 

 produce to be raised. Lucern, which shoots out roots 

 four or five feet in length, requires deeper ploughing than 

 corn, whose roots are very superficial. Six or eight 

 inches is sufficient depth for grain in general. 



Emily. When new land is first broken up, to bring it 

 under tillage, it will, I suppose, require deep ploughing 

 to pulverise the hard earth. 



Mrs. B. That also depends on the nature of the soil. 

 In America, where fine rich vegetable soil is daily brought 

 into cultivation, nothing more is required than to scratch 

 the earth with a plough, and scatter the seed, in order to 

 produce an abundant harvest. But in England, and all 

 countries which have long been cultivated, the good soil 

 is already fully employed ; and if any new land is plough- 

 ed up, it is of a very inferior description, and it is neces- 

 sary not only to plough it deeply but repeatedly, and to 

 manure it, before it will yield a crop. The operation of 

 bringing grass land into tillage is on the Continent fre- 

 quently performed by a pickaxe with a double prong, 

 which breaks the earth more completely than the plough. 



Another point to be considered in tillage is the quantity 

 of manure to be spread upon the land. If this fall short, 

 and the ploughing has been deep, the nutritive particles may 

 filter down lower than the roots can go in search of them. 



874. What is said of mixtures of clay and sand 1 ? 875. If there be 

 a good, rich, vegetable soil on the surface and layers of sterile ground be- 

 neath, what should be the mode of ploughing 1 ? 876. How is the depth 

 of ploughing to be varied from the nature of the produce! 877. In 

 America what is the nature of the soil, and the mode of ploughing 1 ? 878. 

 And in England! 879. What is another ooint to be considered in tillage! 



