410 



SCIENCE OF AGRICULTURE. 



Part II. 



the central one (which is fixed) can be varied from nine to ten or eleven inches ; and that 

 the two small wheels may always be at the same distances respectively as the conductors, 

 there are two washers (hollow cylinders), an inch in breadth, on the axle-arms of each, 

 which may be transferred either to the outside or inside of the wheels, so as to make their 

 distances from the outside conductors nine, ten, or eleven inches respectively also. 

 The small wheels may be raised or depressed, so as to alter the depth at which the seed 

 shall be deposited, by the action of a wedge, which retains the upright part of the axle 

 in any one of a number of notches, which are made similarly in both, and which are 

 caught by an iron plate on the upper side of the arms which carry the axles. This 

 machine may be still farther improved by increasing the number of conductors to five 

 instead of three ; the latter number giving too light work to the horses. {Highland Soc. 

 Trans, vol. vii.) 



2683. Of bean dri'ls there are three kinds, all equally good : one for sowing in prepared 

 drills or after the plough, which is pushed by manual labour, and has been already 

 described (2574.) : one attached to a light plough, which draws a furrow in prepared soil, 



and sows a row at the same time 

 {Jig. 342. ) ; and one which can be 

 fixed between the handles of any 

 common plough for the same purpose. 

 The former has a wheel (a) to re- 

 gulate the depth of the furrow, and a 

 lever (6; to throw the drill out of gear 

 on turning at the ends of the ridges. 

 It is a useful and very effective im- 

 plement ; though a skilful plough- 

 man will effect the same object by a 

 drill placed between the handles of a common swing plough. 



2684. Web's expanding bean drill to sow four rows is affixed to a pair of wheels and 

 axle, in the manner of Cooke's drill. The axle which passes through the drill boxes has 

 four movable brushes and cylinders, by which means any widths, v.ithin that of the axle, 

 can be given. Where ground is prepared and ribbed, and where there is not a Cooke's 

 drill on the premises, this machine may be resorted to with convenience. 



2685. The block-plough drill is an equiangular triangular block, 30 inches to a side, 

 with cast-iron scuffler teeth and wooden blocks slipped over them. A field being ribbed 

 or laid up in ridgelets with this implement, is next sown broadcast with wheat and 

 bush-harrowed, by which the grain rises in rows, as accurately as if sown with the drill. 

 (Farm. Mag. vol. xxiii. p. 406.) 



2686. Machines for dibbling beans, impelled by manual 1 :bour, have been already noticed 

 (2574.). A horse dibbling machine (Jig. 343. ) has been invented, though very little used, 



<Bi oia t^ 



and being rather complicated in its movements, it will require considerable simplification 

 before it can be recommended. A heavy cast-iron roller, with protruding angular rings, 

 might form drills for the beans, and, probably, some machine of this sort might distri- 

 bute them singly or neariy so, and at regular distances : but the best cultivators prefer 

 sowing in drills, more thickly than in dibbling, in order to admit of a wide interval for 



