Book IV. 



HARROWS. 



415 



greater weight and dimensions than necessary for ordinary soils. Its use is to reduce the 

 stronger clays, at a time when they are too obdurate to be impressed with the teeth of 

 the common harrow. The levelling brake, or grubber, is generally considered the 

 preferable implement for this purpose. 



2701. The brake, grubber, or levelling harrow (fig- 354.), is a valuable implement on 



strong clayey soils. It consists of two frames, the 

 one triangular and the other oblong. I3y means of 

 the handles, the oblong part of this brake can either 

 be raised up or depressed ; so that when the ground 

 is cut in small pieces by the teeth of the triangular 

 harrow, then the oblong harrow following, its teeth, 

 being pressed down into the high parts, carry or 

 drag part of the soil oft' from the heights ; and, 

 when they are raised up by the handles, leave that 

 soil in the hollow or low parts. By this means, the 

 •round is brought nearly to one plain surface, 

 whether that surface be horizontal or sloping. 

 Sometimes it may be found necessary to place a 

 greater number of teeth in the oblong part of the 

 brake, so that they may be nearer to one another, 

 and perform the operation more effectually. The 

 teeth are made sharp or thin on the fore edge, for 

 cutting ; broad and thick on the back, for strength ; 

 and tapering, from a little below the bulls to their 

 joints. 



2702. Morton' s revolving brake harrow (Jig. 355.) 

 is a very powerful implement in strong clayey soils 

 infested with couch. When the implement is to be 

 moved from one field to another, the large wheels 

 may be brought forward (a), to support the tines 

 from the "-round, while the hind axle and the rake are supported by a castor or truck- 



wheel (b). In most soils, four horses and a driver and holder are necessary to work 

 this instrument ; which, however, no good farmer will ever require the aid of, unless it 

 be when entering upon land which has been allowed to run wild, or clay of an extraor- 

 dinary degree of tenacity. We have seen it extensively and advantageously used, on 

 the latter description of soil, by Mr. Dickson of Kidbrook farm, Blackheath, Surrey. 

 (Gard. Mag. vol. iv. p. 186.) 



2703. As substitutes for the last two implements, may be mentioned tinlaysons 

 harrow (2657.), Wilkie's brake (2656.), and Kirkwood's improved grubber, which will 

 be afterwards figured and described, the invention being only made public while the 

 present sheet is passing through the press (February 15.). Bartlttt's cultivator, Brown s 

 cross-cutting machine/the Sythney scarifier, and the spiky roller, noticed in next section, 

 are used for a part of the purposes of the last two implements. 



