Chap. XX. Of the Drill-Boxes. 339 



the Surface of the Tongue oppofite againft it. Thefe 

 Two Surfaces meeting one another below, when the 

 Tongue is fet up clofe to the Spindle, form a mix'd 

 Angle, which flops up the Seed-pafTage, except 

 when a Notch comes againft it. 



When the Tongue is fet from the Spindle, to the 

 Diflance of feveral Diameters of one of the Seeds 

 that are to be drill'd, this revers'd Bevel caufes the 

 Seed to arch at the Seed-pafTage, and flop there, till 

 the Notches force it thro', which would, without this 

 Arching, fall out by its own Gravity, without the 

 Turning of the Wheels. 



The Seed arches here the more firmly, the more it 

 is prefs'd upon by the incumbent Seed from above it; 

 and the former Bevel (which I call the Bevel of the 

 Mortife) permits the incumbent Weight to prefs the 

 harder on the Seed that is near the Seed-pafTage ; and 

 this might be reckon'd a fifth Ufe of the former 

 Bevel : For as it prevents the Seed from arching in 

 any other Part of the Mortife, fo it does, by the 

 fame means, caufe it to arch the more ftrongly at the 

 Seed-pafTage, which is fcmetimes (viz, when the 

 Tongue muft be fet wide) as necefTary, as it is for 

 it to efcape arching before it comes thither. And 

 the more ftrongly this Arch prefTes againft the Tongue, 

 the more the Tongue by its Spring prefTes againft it ; 

 and this Preflure being reciprocal and equal, the Seed 

 cannot fall out fpontaneoufly •, for when the PafTage 

 is thus wide, if you throw into the Mortife a few 

 Seeds, fuppofe Five or Six at a time only, they will 

 all pafs through immediately, without any Motion 

 of the Wheels ; but if you throw in a large Quantity 

 together, there will only a few of the lowermoft fall 

 through, unlefs the Wheels do turn and throw them 

 down by the force of the Notches. 



Indeed we do not care to fet the Tongue fo very 

 wide from the Spindle, unlefs it be when we are ob- 

 liged to plant a very much larger Proportion of Seed 



Z 2 than 



