dur'm(y the last Four Years. 191 



o 



I have dwelt at great length on the construction of the plough, 

 because each successive trial has shown that it is a subject 

 which rewards our inquiries in practice. Mathematical calcula- 

 tions have been framed for it, but the mouldboard of Lord Ducie's 

 plough, so highly praised by our judges at Bristol, had been cast 

 on the day before the trial from a mould shaped to the actual 

 curve of the furrow-slice : and it may be best thus to fit on the 

 plough to different kinds of soil. There is evidently much to 

 be gained, and a great reduction of horse-labour to be effected. 

 Only we must not go too far by asserting that all land can be 

 worked at all times by two horses only.* Soils differ much too 

 widely in their resistance, as appears from the following numbers, 

 which have been already published,! showing the average draught 

 of numerous ploughs tried by me on three neighbouring farms : — 



Draught. 



Sandy loam ... 17 stone. 

 Clay loam .... 30 

 Strong clay ... 47 



Mr. Hannam too, in his interesting trials, has shown that the 

 sam.e field, in different stages of cultivation, varies widely in its re- 

 sistance ; for he measured the draught of some ploughs during 

 the process of barley-sowing, and the difference wilh Hart's 

 plough was as follows : — 



Draught. Furrow. 



April 2. Seed-furrow with single horse .... 9 stones 2^ X 8 

 April 3. Breaking up turnip-grouncltrodden in rain 21 5x9 



„ Ditto less trodden 18 5x9 



April 20. Ditto drier and harder, with the same 



plough 25 5J X 9 



The difference of draught between three farms worked with the 

 same ploughs was one to three, and here on the same field the 

 difference within one month is again one to three. Such varia- 

 tions must encourage active inquiry, but should check hasty con- 

 clusions. 



There is no doubt, however, that in many parts of the country 

 the third horse might be discarded, and that two horses would be 



* Even if two horses could draw the plou*^h in winter on our heavy clay- 

 lands, the surface is so soft that the horse which must necessarily walk upon 

 the unploughed land does great harm by trampling it together. I believe that 

 the best plan upon such farms would be this : to have a plough wilh two 

 shifting mouldboards, a short iron one for summer use, wilh two horses 

 abreast, and a long wooden one for wet weather, to be used with three 

 horses walking in line. Both Mr. Bennett of Tempsford, near Bedford, 

 and Mr. Moore of Coleshill have adopted this plan of a changeable mould- 

 board. The plough should have one wheel in summer, and in winter d^foot, 

 which clogs less than a wheel. 



t Journal, vol. i. p. 219, Inquiry on Draught in Ploughing. 



