PLO 



PLO 



one of which is perforated nearly its 

 wliole length by a dovetail-shaped 

 groove, for the reception of a sliding 

 piece, to which the second scale is 

 attached, and witii which it moves, 

 the edge of the second being always 

 at rijiht angles ti) the edge of the first. 

 By this means the rectangular co-or- 

 dinates of a point are measured at 

 once on the scales, or the position 

 of the point laid down on the plan." 

 — (Bramle's Ena/dopcedia.) 



PLOUGH AND PLOUGHING. 

 " Before we enter into any details, it 

 may be as well that we describe the 

 diflerent essential parts of a plough 

 by the names which are usually given 

 to them. 



" The body of a plough is that part 

 to which all the other parts are at- 

 tached. Tlie bottom ol' it is called 

 the suU, or slack, to the fore part of 

 which is affixed the point, or share ; 

 the hind part of the sole is called the 

 hcd. The beam, which advances for- 

 ward from the body, serves to keep 

 the plough in its proper direction, and 

 to the end of it are attached the oxen 

 or horses which are employed to 

 draw it. Fixed in the beam, in a 

 vertical position, before the point of 

 the share, with its point a little for- 

 ward, is the coulter, which serves to 

 cut a vertical section in the ground, 

 while the point of the share, expand- 

 ing into a Jin, separates a slice by a 

 horizontal cut from the solid ground 

 under it. The mould-board, or turri- 

 furrow, is placed obliquely behind the 

 fin, to the right or left, in order to 

 push aside and turn over the slice of 

 earth which tlie coulter and share 

 have cut off: it thus leaves a regular 

 furrow wherever the plough has pass- 

 ed, which furrow is mtended to be 

 filled up by the slice cut off from the 

 land by the side of it when the plough 

 returns. The stilts or handles, of 

 E 



Fig. 

 c 



which there may be either one or two, 

 as is thought more convenient, direct 

 the plough by keeping it in the line 

 required, and at a regular depth in 

 the ground. The single stilt appears 

 to be the most ancient form. 



" Wheels are a n)odern invention 

 in.comi)arison with the other parts. 

 They support the end of the beam, 

 and prevent it from going too deep 

 into the ground, or rising out of it 

 while the plough is going on. The 

 greatest improvements introduced 

 into modern ploughs are in the shape 

 of tlie mould-board or turn-furrow, 

 of which we shall lake particular no- 

 tice, and the contrivances for regu- 

 lating the line of draught, so as to 

 make the plough go at an equal depth, 

 and cut off a regular slice of equal 

 breadth without any great force being 

 applied by the ploughman who holds 

 the stilts. 



" The ploughs in use in different 

 countries in Europe have undergone 

 little change for many centuries ; it 

 is only lately that any attempt has 

 been made to vary the old forms. 



"The Roman plough, such as is 

 described by Virgil in the ' Georgics' 

 (i., 169), is still used in many parts of 

 France, under the name of Araire 

 Remain. It consists of a beam {te- 

 mo), a body {buris), a share {vomer), 

 and a handle or stilt {stira). The of- 

 fice of the turn- furrow is performed 

 by two pieces of wood, about six inch- 

 es long, projecting obliquely upward, 

 and very properly called teeth {dcnia- 

 I lia), E F {Fig. 1). The sole of the 

 , plough, A B, has two pieces of wood, 

 G G and D H, fixed to it on each 

 side, forming an acute angle with it, 

 in which the teeth are inserted. This 

 exactly answers the description of 

 Virgil, ' Duplici aptantur dentalia dor- 

 se' (the teeth are fitted to the double 

 back). 



590 



