35G 



l^cporl on the Exhibition of ImjAemcnis 



was less than that of his swlno: plough by 4 stones, the latter 

 equalling a new and very elegantly constructed swing-plough from 

 the workshop of the Earl of Ducie, to whom the prize was ad- 

 judged, as the quality of the work done by the latter was consi- 

 dered to be superior, in a slight degree, to that of the other ploughs 

 of this class. 



Surface pulverizing plough. — The judges have to report, in 

 addition to the trials of these well-known varieties, the perform- 

 ance of an implement constructed by Mr. Mason, of Grafton, 

 Warwickshire, which, as a common wheel-plough, did excellent 

 work ; but its peculiarity consisted in the addition of pulverizing 

 knives attached to moveable bars, or rods, extending beyond the 

 end of the mouldboard. These knives are used in suitable soils 

 for cutting off the angular summit of the furrow-slice just raised, 

 and dividing it into two, or, if requisite, into three portions. 

 Having ascertained the draught of this plough in its ordinary state 

 (see woodcut, fig. 1), one of the knives, a, was put in work to 

 about the depth of '2 inches below the surface of the slice ; and 

 then a second knife, acting at a somewhat greater depth below the 

 upper one. Under these conditions the dynamometer exhibited 

 an increase of draught of 4 stones, or a little more than 15 per cent. 

 The skim-coulter, b, was then set down to the depth of about 

 an inch : this did not appear to cause any increase of resistance. 



The woodcut shows the plough in perspective, with sufficient 

 accuracy to illustrate the position of the knives, when out of work, 

 and the simple arrangements for holding them and adjusting their 

 depth of cut. Their shape is as drawn, but it will be understood 

 that, when at work, their curved cutting edge is presented, at an 

 angle more or less acute, to the furrow-slice, which is divided 

 horizontally, in the plane of the plough's path. 



Fi-. 1. 



The character of the soil upon which the trials were made 

 was that of a sandy loam in a good mellow state, a crop of 

 strong clover having been cut from it on the preceding day. The 

 appearance given to the surface of the ploughed land by the 

 action of the knives was that of a well-harrowed field, the soil 

 being left loose and pulverized nearly to the depth turned up. 



