302 EXPANDING HARR0W8. 



XIT. 



Description of a Pair of Expanding Harrows, appUcahle 

 both for cleaning foul Land, and harrowing in Seeds. By 

 Mr, AViLLiAM Jeffery, of Cotton-End, Northampton*. 

 SIR, 



New invented -IL HAVE sent, for the Society's inspection, a model of a 

 harrows. ^^\^ of harrows of my own invention, made to a scale of one 



inch and a half to a foot, and which are allowed to be a 

 great improvement in these implements. 

 The improve- The improvement consists in their power of contraction 

 or expansion, so as to cover an extent of land from five feet 

 to ten feet; their teeth may be set at twelve different dis- 

 tances between them, and their tracks will always be at 

 equal distances, according to the state of the land ; they 

 will either servefor harrowing in seeds, or cleaning foul land. 

 For cleaning foul land this harrow far exceeds any other 

 yet made; for in such land the teeth ought to be at a 

 greater distance in the first harrowing, and at the subse- 

 quent harrowings to be brought nearer together by degrees, 

 till the teeth are brought very near together by contracting 

 them. One pair of my harrows ansiver the purposes of 

 three or more pairs made upon the old construction with 

 fixed teeth. 



My harrows are so constructed as to be contracted, or ex- 

 panded, in two or three minutes; and the teeth, which are 

 thirty-four in number, set at any equal distances required, 

 having only two screws to confine them. This implement 

 is more durable than other harrows, as there are no 

 mortices or tenons in them to weaken the wood-work, or 

 admit the rain. Theyare puttogether with iron nuts and screws. 

 They are also easier conveyed from field to field than 

 other harrows, and when not in use will fold up in a 

 small <?ompass. I hope they will meet the Socfety's appro- 

 bation, and be rewarded according to their merit. 

 I remain. Sir, 



Vour humble Servant, 

 Cotton-End, Northampton, WILLIAM JEFFERV. 



June 8, I8O7. 



♦ Tnuii. of Sec, of Arts, vol. XXVllI, p. 51. The silver mfdal was 

 ▼oted to Mr. Jeffery. 



On 



