HARROWING. 47 



fore, travels the country with it at seed-time, and under- 

 takes to sow the seed of any farm, where the farmer may 

 require his services. He does this at so much per acre ; 

 the farmer supplying the horses, and undertaking to 

 deliver the machine on the farm where it is to be next 

 employed. 



When the seed has been committed to the earth, 

 whether broad-cast or by drill, the harrows immediately 

 follow the sowers, and complete the work. 



The harrow is one of the simplest of agricultural 

 implements, and appears to have been used at a very 

 remote period, nearly in its present form. It consists 

 of a simple framework of wood, having four stout bars 

 placed lengthways, and the same number of lighter bars 

 placed crossways. Into each of the former are fixed, 

 at intervals, iron spokes or tines, which act as the teeth 

 of a rake, in breaking up the surface of the ground, and 

 covering in the seed. Two harrows are commonly 

 coupled together in working, and thus a greater sur- 

 face of ground is covered. The horses are attached 

 to this implement by means of a system of chains 

 and hooks, connected with horizontal bars called swing- 

 trees. 



Harrowing appears to be a very simple operation, and 

 would seem to need scarcely any effort on the part of 

 the horses or their driver ; but it sometimes happens 

 that it is a work of considerable labour. The design of 

 harrowing is not merely to cover the seed, but to stir 

 the soil thoroughly, and to bring to the surface, and 

 break asunder, all the larger clods. When the tines or 

 teeth of the harrow are long and well sharpened, and 

 when the horses are kept at a brisk pace, this is very 

 effectually done, the tines taking a deep hold on the 

 soil ; but on this very account the labour is greater for 

 the horses. When the work is well done, the ground 

 feels uniformly smooth, and the clods lie free upon the 

 surface, instead of being half buried in the soil. This 

 uniformity being attained, the harrowing should cease ; 



