On tite Draught of Ploughs. 



17 



the same circumstances, except that the soil had become much 

 harder and drier throughout. 



The fourth trial (April 11th) in which the hard trodden surface 

 had been previously single-horse ploughed and reduced. 



The fifth trial (April 20th) during the stirring for barley 

 (second furrow) with single horse, 4 inches deep, upon a surface 

 harrowed and rolled. 



I made several minor experiments besides, to verify these, as 

 well as for objects not immediately connected with our present 

 inquiry. I made also several trials in order to arrive at some 

 analysis of draught : they were made almost entirely by myself, 

 assisted only by my man. I noted no draught down till my mind 

 was perfectly satisfied about it ; and where there was room for 

 doubt I threw the advantage to the side against which the test 

 seemed to be going. There is a fifth place given to Hart's 

 second mould-board, a whole one, to compare it with its more 

 commonly used open one with detached ground-wrest. 



Comparatwe Experiments with Four light Draft Ploughs. 



While the open mould-board of Hart's was a full stone 

 lighter than the whole one, the reverse was the case with D P, 

 which has a similar form of mould-board to shift. This arises, 

 1 believe, from greater fulness in the breast of Hart's open one. 



7Vie comjmrative Average of each Plough, first, on the three 

 occasions in which they were all engaged together ; then, where 

 three ploughs only were togetheiv throughout, I think will be 

 found as follows : — 



