Chap. XX. Of the Drill- Boxes. 3 27 



Fig. 10. Plate 2. is the Fore-end of a Wheat 

 Mortife, with its Hole A, thro' which the Setting- 

 fcrew is fcrew'd, and paries up to the Back of the 

 Tongue by the Line qr in Fig. 3. 



Fig. 9. in Plate 3. is the hinder End of a Wheat 

 Mortife, which by its prick'd Lines, and the Two 

 right-angled Triangles they make, fhews the Bevel 

 of the Mortife, and alfo its Depth j it alfo fhews the 

 Difference of the Bevel of the Mortife, and that of 

 the Tongue, Fig. 1. which is placed againft it: 

 Theie Figures having been already demonflrated in 

 the Defcription of the Turnep Mortife, and in thefe, 

 1 need fay no more of it, but that I think thefe laft- 

 mention'd Figures fufficient Directions for under- 

 standing and making the Mortife of a Wheat-drill. 



Fig. 3. of Plate 3. exhibits to View a Wheat Seed- 

 box, with its Appurtenances, {landing upon its 

 Bottom ; B the Brafs Cover ; C the Tongue hanging 

 upon its Axis ; c the End of the Iron Screw that 

 holds on the Spring, coming thro' the Tongue, and 

 filed fmooth with it ; ^, 0, #, are Three Notches of 

 the Spindle, with their bevel Ends ; b y £, are Two 

 Interfaces betwixt the Notches. 



Hitherto we have been fpeaking of the Parts 

 contained in the Wheat Seed-box ; let us now come 

 to the Parts containing : As, nrft, d efg is the upper 

 Surface of the Brafs Seed-box, mewing the Top of 

 the Mortife, and what it contains \h h h, and b b b 9 

 fhew the Ends of the hollow Cylinder, and its Bafes 

 coming out on each Side, farther than the Box ; for 

 if it did not project farther out than the Sides of the 

 Box, the Surface of it would be fo narrow, that it 

 would cut the wooden Spindle by the Friction made 

 between it and the Spindle ; but the Surface, being 

 qf this Breadth, never wears into tffe Spindle, but 

 makes it fmooth and mining ; i i /*, and *' i /, fhew a 

 foreign of the wooden Spindle (of an Inch and an 



Y 4 half 



