Sf« APPEND! X. 



long, and as broad as the Thicknefs of the Iron Fittj 

 the End and Nut of which are feen at C, in Fig. i„ 

 This Pin Ihould be more than half an Inch Diameter, 

 and fquare at that End that goes into the Mortife ;' 

 let the hinder End of the Mortife juil appear behind 

 the Plank, when the Beam is at right Angles with it. 



By means of this Mortife there may be many more 

 Holes through the Plank without Danger of fplitting- 

 into one another the Holes* in the Beam, which muft 

 anfvver thofe in the Plank.- 



Draw many Lines from the Middle of the foremoftV 

 Hole of the Plank to the hinder Edge of it, at (fup- 

 pofe) a quarter of an Inch from one another there ? 

 *nd then bore a Hole In that Part of each Line that 

 is leaff. apt to break into the next Hole to k. 



Every Syftem of Holes in the Plank will have like 

 Benefit of being increafed in their Number by the 

 Convenience of this Mortife; without which it is in> 

 pofhble to have fo great Variety of turning the Point 

 of the Share to make the Share go parallel to the' 

 Horfe-path. 



The Board defcribed in p. 403. we now ufe very 

 feldom in Hoeing of Wheat. 



Explanation of Plate \TL 



FIG. 1. mews the Plank and the Harrow of the 

 latefl and belt Drill-plough, moil fimple, and 

 accommodated to the preknt Practice of planting 

 double Rows. 



A is the Plank, with all its Mortifes and Holes; 

 b is the Mortife into which the Tenon of the fore 

 Sheat of the Drill-plough, for planting treble Rows,' 

 was fattened ; d is the fquare Hole for receiving the" 

 Seed from a Hole of the fame Shape and Size in the. 

 Bottom of the Funnel. 



When the Sheat is taken out of the Mortife % and 

 another Sheat is made exactly the fame with that, 

 place them in the Mortify a a^ and make the Two 



fquare 



