Experimental Inquiry on Draught in Ploughing . 231 



disadvantage arises not from their concave mould-l)oard, or from 

 any defect in the shape of their cuttin;^ parts (on the contrary, 

 upon sand they produce the same effect with a power of 7 or of 

 5 stone as Hart's does with a power of 9 stone), but from some 

 cause which makes their own weight tell heavily on the draught. 

 It appears^, too, that the four easiest ploughs in this point of view 

 have hollow breasts, the four heaviest full breasts. Still it must 

 not be forgotten that the trial is on sand, to which the hollow 

 breast is considered to be most adapted. It appears, too, that of 

 the two competitors. Hart's and Ransome's wheeled ploughs, one 

 is singularly easy above ground, and the other below, so that a 

 lighter plough than either for light ground might possibly be 

 formed by combining their peculiar merits. I must add, how- 

 ever, that, although the principle of this calculation generally is 

 simple enough, I am not confident in the details which I have 

 given, because, in repeating the trials as to the surface-draughts 

 of two or three ploughs, they varied much according to the nature 

 of the surface, and also because, excellent as is Mr. Cottam's new 

 draught-gauge, I am not sure that it is quite correct before it 

 reaches 8 stone, or 1 hundred- weight. 



Trial IV.— iVou. 8. 



Although the pair of Scotch horses, and, still more, the other 

 pairs, had been defeated, on the first day, by the heavy clay, it 

 was fair to afford them another trial with stiff land of a less obsti- 

 nate kind than that with which they had then endeavoured to 

 cope. It had been also the principal object of Mr. Morton to 

 prove to two farmers in the neighbourhood that their strong 

 ground, which was usually Avorked with four horses, might be 

 ploughed by two only. The first field, therefore, which we 

 entered on was a deep strong loam, in the parish of Charney, 

 very good for all kinds of crops, resting upon yellow clay, at that 

 time a clean bean-stubble. It offered great resistance to the 

 plough, as the following numbers show. The furrow was 5 

 inches by 9. 







Furrow 5x9 



1. 



Ferguson's swing . 

 Clark's swing 



. 35 



2. 



. 33 



3. 



Hart's one-wheeled 



. 23 



4. 



FF, with wheels . 



. 33 



5. 



FF, swing 

 King's swing 



. 30 



6. 



. 27 



7. 



King's wheel 



. 30 



8. 



Old Berks . 



. 36 



9. 



Kutland, NL 



. 36 



Average . , 31|^ stones. 



