PRACTICAL AGRICULTURE. 53 



are not agreed upon the form and proportions most 

 proper for this instrument. As in other cases, so in 

 this, there may be no abstract perfection; what is 

 best in one description of soil may not be so in an- 

 other ; yet, as in all soils the office of the plough is 

 the same, viz., to cleave and turn over the earth, there 

 cannot but be some definite shape and proportions 

 better fitted for these purposes, and, at the same 

 time, less susceptible of resistance, than any other. 



This beau ideal, this supposititious excellence, in 

 the mechanism of a plough, has been the object of 

 great national as well as individual research. In 

 Great Britain, high prizes have been established for 

 its attainment ; and in France, under the ministry of 

 Chaptal, 10,000 francs, or $2000, were offered for 

 this object by the agricultural society of the Seine. 

 In both countries the subject has employed many 

 able pens ; those of Lord Kaimes, of Mr. Young, of 

 Mr. Arbuthnot, of Lord Somerville, and of Mes- 

 sieurs Duhamel, Chateauvieux, Bosc, Guillaume, 

 &c. It is not for us, therefore, to do more than 

 assemble and present such rules for the construc- 

 tion of this instrument as have most attained the 

 authority of maxims. 



1st. The beam, or that part of the plough which 

 carries the coulter, and furnishes the point of draught, 

 should be as near that of resistance as possible ; be- 

 cause the more these are approached, the less is the 

 moving power required. Even the shape of the 

 beam is not a matter of indifference. In the old 

 ploughs it was generally straight, but a small 

 curve is now preferred; because it has the effect 

 of strengthening the coulter by shortening it. 



3d. The head of the plough is the plane on which 

 it moves. This should be concave, because that 

 form offers fewer points of friction, and, of course, 

 less resistance. Between the beam and the head is 

 an angle, on which depends the principal office of 

 the plough ; the making, at will, a deep or a shal- 

 E 2 



