78 



If the trench plough be sufficiently strong, and a good team of 

 bullocks be available, it will be possible to turn the soil to a depth 

 of 15 inches in a single operation. The ground, after having 

 been subsoiled or trenched, as the case may be, and left exposed 

 during the winter, will have settled down considerably and be almost 

 level. It should then receive a light ploughing and harrowing, when 

 it will be in a fit state for planting. 



Any parts which are sour and swampy (especially in the first 

 region) should be drained. Places of this character should be care- 

 fully marked when observed, and properly drained before being 

 planted with vines. 



The most suitable system of drainage consists of a series of small 

 drains running into larger ones, which in turn empty themselves into 

 main drains situated in suitable positions. 



FIG. 9. 



A glance at Fig. 9 will show the disposition of these drains. 

 The small arrows indicate the direction of the greatest fall, a a, the 

 main drain, which may be situated along a gully, in which case it 

 can be left open, b b b are the secondary and c c c the small drains. 

 All the drains should be so placed as to make as great an angle as 

 possible with the line of greatest slope. This presents the double 

 advantage of not giving too much fall, in which case the scour might 

 be too great, and rendering the drainage more effective. A drain 



