DRAINAGE. 1Q3 



for 5. The minimum price for excavating and refilling a 

 4-feet 6-inch drain is, according to our experience, l^d. 

 per yard. This low price is generally in those clays which 

 require the most frequent drains. The maximum, %^d., 

 except in cases where there is actual rock. The frequency 

 with which the pickaxe is used is nearly an accurate mea- 

 sure of the necessary advance of price. 



Our parting word shall assure our readers, that every re- 

 ported case of failure in draining which we have investi- 

 gated has resolved itself into ignorance, blundering, bad 

 materials, or bad execution. 



POSTSCRIPT. 



SINCE the substance of this Essay was first published, a 

 dry March has afforded us the opportunity of investigating 

 accurately the effects of some drainages executed in the 

 manner which we have recommended. In the winter of 

 1846-7 we drained a portion of an old forest which had 

 never received any culture drains 4 feet 6 inches deep, 

 in the line of steepest descent, parallel, 9 yards apart, the 

 conduit formed of 1-inch and 14-inch pipes collared, the 

 shape of the laud a regular plane, with an inclination of 

 about 1 inch in a yard. Six inches of light brown mode- 

 rately friable soil on a very retentive clay, which passed at 

 4 feet deep into a somewhat opener clay or marl. Surface 

 before drainage plashy in wet weather, and covered with a 

 fuzzy grass, blue in summer and white in winter, on which 

 no animal would willingly graze, and barely worth, to let, 

 5s. per acre. In the first summer after drainage the 

 herbage was visibly improved. In the second autumn the 

 cattle grazed it bare. During the second winter it was 

 covered with a dressing of lime and soil, at an expense 

 rather under 5L per acre. In this, the third summer, it 

 has a very good herbage, and any neighbouring farmer 

 would give for it, to graze only, 25s. per acre. We con- 



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