AGRICULTURE. 



a large extent of clay-land was drained at narrow 

 intervals in Norfolk and Essex, by putting in 

 brushwood and even straw in the bottom of the 

 drains. The progress of this operation, which is 

 now regarded in many soils as essential to eco- 

 nomic culture, was slow and partial, until Mr 

 Smith of Deanston reduced the practice to a 

 system, and shewed the principles upon which its 

 efficiency depended. Through the exertions of 

 this advocate, furrow-draining soon became a sine 

 qud non in the culture of clay soils. 



The great majority of practical men consider 

 the line of greatest fall, or quickest descent, as the 

 best for cutting drains in a field. This, it may be 

 remarked, is also usually the direction for plough- 

 ing the land and forming the ridges ; so that the 

 drains are commonly put into the furrows, and 

 hence the distinguishing appellation, furrow- 

 draining. The smaller drains are conducted into 

 larger or main drains, instead of each discharging 

 its quota of water into the open ditch. This is 

 rendered necessary, as the mouths of the smaller 

 drains would be more liable to be choked up by 

 the growth of weeds ; while the collecting of water 

 into main drains secures a fuller flow to sweep out 

 any matters which might accumulate where the 

 discharge is small. 



The most efficient, and at the same time cheaply 

 cut drain is one represented at fig. 15. 

 It is made so that a pipe of a cylindrical 

 form may be laid along its bottom, which 

 should be of no greater width than what 

 is necessary to its being securely placed. 

 Drains of this form are cut with a set 

 of spades which are of different widths 

 Fig. 15. the broader being used for taking out the 

 top, and the narrowest for the bottom. 

 The one which cuts the last spit is called the 

 bottoming tool, and its introduction has effected a 

 considerable saving in cutting drains. 



Before the general use of pipes, stones were the 

 common materials with which drains were formed. 

 Mr Smith recommended that they should be 

 broken so small that they might pass through a 

 ring two inches and a half in diameter. From 

 nine inches to a foot in depth was the quantity 

 which was commonly put in. This was found to 

 be a most efficient way of making 

 drains ; but unless the stones 

 could be gathered from the fields, 

 or quarried in the neighbourhood 

 where they were used, an im- 

 mense amount of labour was in- 

 volved in filling them. 



When tiles and pipes were first 

 used, it was even thought neces- 

 sary to have some gravel, or small 

 stones, placed above them in the 

 drains, for the purpose of enabling 

 the water to find its way into them, 

 as seen at fig. 16. It was soon 

 found, however, that tile-drains 

 were quite as efficient without 

 any stones or gravel ; and that 

 they were less liable to be choked up, as the clay 

 or earth acted as a filter in preventing the intru- 

 sion of any kind of solid matter. 



Many kinds of tiles and pipes have been tried, 

 but the cylindrical form is now most used. At 

 one time, a bore in the tile of an inch in diameter 

 was thought sufficient, but two-inch tiles are now 



Fig. 16. 



preferred. They are usually made about fifteen 

 inches in length. The continuity of the drain is 

 sometimes maintained by collars, but now their 

 utility is, to say the least, much doubted. 



Much discussion has taken place in regard to- 

 the proper depth of drains, as well as the distance 

 at which they should be placed. Mr Smith at 

 first advocated the making of drains from two and 

 a half to three feet deep, and at intervals of from 

 ten to forty feet, according to the nature of the 

 land. Experience, however, has been gradually 

 favouring deeper drains, at wider intervals. Mr 

 Parkes went the length of recommending a depth 

 of from four to six feet, at intervals of from twenty- 

 four to sixty-six feet. Even on the most tenacious 

 soils with subsoils of till, few now think of having 

 drains less than three feet in depth, though the 

 distance apart should not in many cases be more 

 than from fifteen to eighteen feet 



The mere tenacity of clays is not the element 

 which determines the depth of drains, or the dis- 

 tance at which they should be placed apart. It is 

 now well understood that the success of draining 

 by pipes depends upon the fissures which are 

 produced in the subsoil by the droughts of sum- 

 mer never entirely closing up ; and thus minute 

 channels are formed which lead the water into 

 the drains. The coarse tenacious clays which are 

 to be found in the chalk-valleys of England crack 

 readily by the droughts, and form deep fissures,, 

 which render them comparatively easily drained. 

 On the other hand, in the moist climate of Scot- 

 land, the subsoils which are of //// are long in 

 cracking ; and the drains in such land should not 

 be so deep, and at shorter distances apart. As 

 the properties of clays become better understood 

 and classified, practical men will soon come to be 

 more at one in regard to this important point con- 

 nected with the economy of drainage. 



The principal advantages of drainage are, the 

 deepening of the staple soil and rendering it more 

 friable, so that a superfluity of water which would 

 cause the formation of those chemical compounds 

 that are found in stagnant water is prevented. 

 The greater depth of mould, and more perfect 

 culture, render the soil more absorbent of moisture 

 in dry periods of weather. As crops can usually 

 be sown sooner on drained lands, they also ripen 

 earlier, and produce more abundantly. In short, 

 while drained land obtains a greater capacity for 

 moisture and manure, it imparts to plants greater 

 capabilities for economically working up the 

 materials which they find both in the soil and 

 atmosphere, seeing they are maintained in the 

 most healthy conditions of growth. 



Green Crops. 



Grasses, as seen in perfection in rich lawns or 

 meadows, are the most beautiful crops that grow. 

 The constant carpet of verdure which these pre- 

 sent in England, is owing to the great number of 

 varieties which come to perfection at different 

 periods of the year. In sowing out fields for 

 permanent pasture, we do well to take a lesson 

 from nature, and sow a mixture of grasses which 

 are valuable, and at the same time indigenous to 

 the soil ; for although those grasses which are 

 best suited to the soil will often, in a series of 

 years, take possession of it, yet time is gained by 

 anticipating nature. 



