C0 7: TF ye. 8,

PAGE, Surface wetness, from the retentive nature of soils and peculiarity of situation, removed by hollow superficial drains properly formed-- 290 In grass land 4 ee DIG In arable land P ibid: METHODS OF DRAINING BOGGY LANDS- 201 Circumstances on which it depends i in diffe- rent cases: sp ibide Manner of levelling for- 292 note. Different directions of the strata produce differences in-»' 205 Means of ascertaining the principal spring, in cutting drains-. 204 Effects of cutting them improperly. ibid. Cutting in cases of irr-gular banks-. 205 Mode of draining in narrow confined bogs, where the porous stratum contain- ing the water unites at but little depth below the retentive material- 206 In those of a more extensive kind 5 7

In marshy or hollow lands adjoining rivers ibid

Medes of forming the drains in these cases. 299 Kinds of most useful- 301 Sorts of materials employed in filling them 302— 323

Nature of bricks used in constructing

them ibid. 326 What requisite to be attended to in putting in the earth afterwards;. 303 Signs of stoppage of- aa toi: Mouth of drains to be guarded 2- ibid. Circumstances which show the drains to be effectual e*aibias

Method of drainage where the ades stratum

is porous, different from‘hat of those

just described 3- 304 Drains to be made in the most depending

parts, through the upper surface soil

to the reientive stratum: 2 Abide Boring then necessary to let down the water. 305 Same purpose eff cted by deep pits or wells ibid. Drains in those cases to be made narrow, and

filled w.ih stones ao Os Attention necessary in forming the ridges,

when the land is to be in tillage S iDid; Nature of porous stratum first to be ascer-

tained::=. bid. METHODS OF DRAINING HILLY

LANDS 3. 306

PAG! Drainage of hills or elevated pasture- grounds, what necessary to be attend- ed to in;. 306 Drains made according to the position of the strata:- 10Id. Trenches necessary to be formed high up in the wet soil, to intercept the springs. 308 Other cuts lower fae requisite in some cases a et Die Both sides of hills may often be drained by cutting into the dryer:> iid. Houses conveniently supplied with water in such cases ee toids May sometimes be raised e a great heightin.“- 309 The cuts or bores not to be made too deep in these cases ibid. METHODS OF DR AINING MIXED SOILS::. ibid. Reason why more generally expensive 5 bids Manner of cutting the drains in. ibid. Means of ascertaining the best situation for-° 5 Sie Modes of in several varieties, described 311 Reason why the drains should be cut in a horizontal direction; ole Fewer drains necessary in these soils a ibid Cause of, explained ibid. METHODS OF DR. AINING RETEN- TIVE SOILS;=; bid. Of forming the drains in the different cases 313 By the plough, or the spade ibid. 318, 319 Other cases of~ 313 Implements made use of in cutting them 320 The miner(see p. 12). 322 Best season for making them.. ibid. Size of, in different instances a- 323 Materials for filling them; ae bids Expense and duration of, in different cases 324 note, 32 METHOD OF DR AINING. MINES, QUARRIES, AND PITS sey Circumstances to be attended to in different cases- 328 By cutting off the springs ibid. By letting the water down into the porous stratum below: oe ibid: Uses to which water mav be converted in some instances of this kind 33G Observations on draining in general ook