38 BRITISH HUSBANDRY. [Ch.III. 



heavily as to be sufficient work for six oxen: they thus crush the clods with 

 great effect; but tliey are more commonly used under the name of rZr//^ 

 rollers*, as they are occasionally employed without weights in broad-casting, 

 to ensure a more regular distribution of the seed. 



From this it is evident that farmers ought to be provided with rollers of 

 different length and diameter, or, if tliey have only one, that it should be 

 so constructed as that its weight may be either increased or diminished to 

 suit the purposes to which it is to be applied. In the opinion of many in- 

 telligent persons, they should not be less than about 16, nor more than 30 

 inches in diameter ; and the best length, if in one piece, is 5 feet, but if 

 double, from 6 to 7. Their importance is indeed too apparent to need 

 ihustration; for, without them, the process of tillage upon strong land can- 

 not be comj)letely executed, and light soils are by their operation rendered 

 more compact and solid. Rolling is essential to most summer crops after 

 the seed is sown, and particularly to wheat in the spring, for the winter 

 frost frequently throws the roots out of the ground, but the pressure of the 

 roller fastens them in the soil, strengthens tlie stems, and occasions them 

 to tiller. It is, however, hn})roper to roll wheat at seed-time, for it is better 

 that the surface of tlie ground be left rather uneven during the winter, as 

 the water passes through it more freely than if it be compressed, and the 

 plants are more effectually preserved dry. 



A roller of the common size will go over about six acres in a day ; where- 

 fore, upon large farms, more than one should be employed to guard against 

 delay in bad weather, for the operation should never be performed when 

 the land is wet. 



Chapter IV. 

 ON THE OPERA.TION OF PLOUGHING. 

 It has been justly observed by Marshall, that to set a plough correctly is, 

 perhaps, one of the most difficult lessons of ploughmanship. One field is 

 of rich, mellow land, ploughable wilh a pair of horses and whip reins, while 

 another is a gluey clay that is hardly manageable with four, and different 

 parts of the same field may often require separate modes of ploughing. The 

 plough, even if the same be used, must therefore be set in different ways, 

 both in the distance of the coulter from the breast, the fixing of the mould- 

 board, and the placing of the swingle-trees in the muzzle of the beam, so 

 as to suit the various depths to which the land is to be ploughed and the 

 breadth of the furrows, according to the tenacity or to the friability of the 

 soil. All this requires different kinds of management, which can neither be 

 conceived by theory nor described by writing, and can only be learned by 

 practice ; it would therefore be a useless waste of labour were we to offer 

 any directions on that portion of the subject, it has indeed been shrewdly 

 remarked, that " voluminous works have been written upon agriculture by 

 able, scientific men in various ages of the world ; and the theory of the art 

 may be said to be well understood, particularly in what are called the im- 

 proved districts of these kingdoms. The pr;ictical is, however, but iniper- 

 iectlv understood by any others than the operative labourers; one man, by 

 dint of experience, obtains a complete knowledge how to set a plough to 

 go steady, and how to hold it straight ; another, how to drill or to sow 

 broadcast ; a third, how to reap, mow, and stack ; others, how to cut an 

 under-drain in a proper direction to carry off" the water ; some, to hedge 



* See the Reports of Leicehtersh., p. 58; Derbysh., vol. ii. p. 46; Oxfordsh., p. 77; 

 and Norfolk, p. 58. 



