Chap. rir. O F H O R S E - H O E S. 443 



iron, to prevent its being worn by the conthiual fridion of the 

 earth. 



This general dafcription feems fufficient : for we believe one may ufr 

 indifferently any common plough that has a mould-board, provided 

 the fore-carriage and wheels be taken off, and tvv'O Ihafts fubftituted 

 in their ftead, like the following. 



KL, are two light fhafts, which are faflened together by the crofs 

 ftaff MN, at fuch diilance as to leave convenient room for a horfe, 

 'OP, is another crofs ftaff, the ends of which reft upon the fhafts, 

 •to which they are faftened by two iron pins. The end of the beam 

 refts upon this crofs ftaif. 



It is eafy to conceive, that the nearer this crofs ftaff O P is fet t«» 

 the other crofs ftaff MN, the deeper the fliare will penetrate into 

 the earth: and the farther thofe ftaves are afunder, the lefs deep the 

 plough will pierce. Either of thefe is eafily done, by fhifting the pins 

 of the crofs ftaff O P to the fuitable holes in the lliafts. 



^R is the neck of this plough, which receives the beam through 

 a round opening, wherein it turns with eafe to the right hand or the 

 left, but ou^t of which it cannot flip, becaufe it is ftopt by a ftrong 

 iron pin driven through it. 



This neck is formed of two feml-cylindrical pieces of wood, 

 which are preffed one againft the other by two fcrew trunnions; and 

 two other trunnions ^R, fix this cylinder to the ends of the 

 fhafts. 



As the cylinder turns upon the trunnions at its ends, the pofition 

 of the beam may of courfe be altered at will, fo as to make the fliarc 

 cut more or lefs deep into the earth : and as the beam can turn in its 

 neck, the plough may be inclined more or lefs to the right or left ; 

 which is neceffary in order to plow well. 



S E C T II. 



Defcn'ption 0/" M. de Chateau-vieux'j Single Cultivator. 



AFTER having feen, fays M. de Chateau-vieux, the effedls 

 •*^ of my plough for ftirring the alleys between the rows of corn, 

 I imagined that the inftrument I am going to defcrlbe, which is much 

 lighter and more fimple in its make, would anfwerthe fame end; or 

 at leaft that it might be uled alternately with the plough, employing 



L 1 1 2 this 



