Cultivation of Moorland. 371 



island the superficial inclination is less important than that of the 

 dip of the strata. These lands are generally composed of materials 

 lying in a stratified order, and in oblique or slanting directions 

 downwards. Some of these strata are capable of admitting water 

 to percolate through them, while others are altogether impervious, 

 and thus force it to filtrate near the surface, and in that way 

 conduct it to the mox'e level lands below, and render them moist 

 and swampy. The rocks, or strata which constitute hilly or 

 mountainous tracts are often found to be continued in much 

 greater regularity than others. The rain that falls, as also the 

 condensed moisture, thus sinks through the superficial porous 

 materials and passes on to the closer strata at a lower point on 

 the sides of such elevations, until it is retarded by some impene- 

 trable substance, such as tight rock or clay. At this stage it 

 escapes at some low position, and oozes out in the shape of 

 " springs," which sometimes appear at a uniform level for a 

 great distance along a hill-side, poisoning all the ground below 

 them. Tliese springs are governed in their discharge by the 

 extent of the hiirh ground on which the moisture is received and 

 detained ; while bog-springs are those that empty themselves at 

 the foot of high eminences, and form swamps and morasses. 



The object to be attained in draining these bog-lands is not 

 therefore to catch the surface water, but that which flows from 

 the spring-head. For this purpose it is necessary to cut a deep 

 " open drain " from bottom to top of the valley, commencing at 

 the lowest possible level, care being first taken that the washings 

 of these open drains be conveyed by " water gutters " to some 

 adjacent dry hillside, as by a little management nearly the whole 

 of the soil to be removed from tlie open cutting may be washed 

 away by the passing current, rather than litted up to the adjoining 

 bank, which by reason of the pressure upon the bank side too 

 frequently runs in again. 



On reaching the head of the bog or SAvamp care must be taken 

 to " drive up " a deep and efficient level to the " spring-head," 

 for tapping and carrying away the stream that there issues from 

 the "tight rocks." This deep cutting will prevent the escape of 

 any water into the old underground drains or currents. 



This main outlet should tlien be left for a time to settle, and to 

 afford an opportunity for observing what amount of good has 

 l)e('n a.complisiied, and what remains to be done. 



The-alter process is to tap all sjirings that remain at the sides 

 or otiierwise, and so condiu I them as to emptv into the permanent 

 open drain. 



For cutting these drains through peaty soil, and say I) inches 

 into the fixed strata below (to prevent the possibility of the water 

 slipping the drain), we usually pay at the rate of 2d. per foot 



