SPRING. 



the principal fprin£rs, and may by this means render the lower 

 drains, on the different fides of tiie main conducing one, un- 

 iieccfTary, unlefs merely to cxtraft the partial lupply of 

 water which the lower fand-bcds may rtceive in time of 

 rains, and which, where thef- fand-beds are of fmall extent, 

 can do little injury to the adjoining furface. From this it 

 appears, that one fpring rifmg in the highclt ground may be 

 the fole caufe of injuring a coufiderable tract lying below ; 

 from its water overflowing the furface at one place, and fnb- 

 fiding into it at another, according to the tenacity or open- 

 ncfs of the foil ; and therefore, in fuch cafes, the upper 

 Ipring. or feeder, fhould be firtt cut off, and the effect of that 

 known, before any more drains are made in the lower 

 ground. 



Befides foils correfponding to this defcription, there are 

 others nearly of a fimilar nature ; but each bed being of 

 lefs extent, and lying more regularly together, their drainage 

 can be more eafily effefted, by means of lels cutting, and 

 confequently lefs expence. Under the beds of fand and 

 clay tliat thus lie alternately together, and almoft parallel 

 to one another, is found a general body of impervious 

 clay, that keeps up the water contained in the fand, which 

 •ontinues always full, moiftening the adjacent clay, and, in 

 A't feafona, running over it. As this main untier/Iralum oi 

 ^Iiy is feldom above four or five feet below the furface, a 

 drain muft be cut to that depth through die middle of the 

 field, if it have a defcent from both fides ; or, if the ground 

 declines all to one fide, the drain mull be cut there, where 

 the water will more eafily difcharge itfelf into it ; and, un- 

 lefs the field is of a confiderable extent, and have more 

 hollows in it than one, one drain will anfwer the purpofe 

 effeftually ; for, by croffing all the different beds that hold 

 the water, it will draw it from each. 



The great difficulty, however, in draining lands of this 

 defcription, and which is imprafticable by one drain, is, if 

 the direftiin of the alternate beds of clay and fand We acrojs 

 the declivity of the grounds ; fo that one drain, in this cafe, 

 can have no other effi^dt than that of carrying off the water 

 after it has pafled over the different llrata, and would here 

 naturally llagnate in the lowell part of the field, if there was 

 no other outlet for it : therefore, when the ground lies in 

 this manner, which is often the cafe, befides the drain in the 

 hollow, others mull be cut up from it, in a floping diredtion, 

 acrojs the declivity, which by eroding all the different veins, 

 or the very thin and narrow ftrata of fand, will extraft the 

 water from each. Where thefe alternate flrata are of great 

 extent, and the wetncfs produced by greater fprings forming 

 fwamps at different levels on the fide of the hills, the method 

 of draining them has been already defcribcd. 



The firit thing to be obferved, in the drainage of fuch 

 alternate (oils, is to difcover minutely the inclination of the 

 alternate ftrata, or how they lie with regard to the fituation 

 of the field to be drained, as upon this the diredlion of the 

 drain entirely depends ; and as the external figns that dif- 

 tinguifh the different beds are eafily perceptible, from the ap- 

 pearance of the furface, and difference of the herbage that 

 each produces, there is little difficulty in attaining this part 

 of the object. In drains of this kind there is feldom any need 

 for applying the auger, as the neceffary depth of the trench 

 reaches far enough down ; and as there is no fpring for 

 want of connetlion with the higher ground to force itfelf 

 up throui:;h the augtr-holes, or, if there is, it cannot, at fo 

 great a depth, and below fuch a body of clay, do any injury 

 to the ground above. 



The drain, after being formed like a fough at the bottom, 

 or fet like a triangle, mult be filled a confiderable way up 

 \vith fmall floncs, before the mould is thrown in, taking care 



to have tcug/j fods laid immediately above the former. 

 Where (tones are fcarce, and plenty of brufh-wood at iiand, 

 faggots may be finiftituted in their place with propriety. 

 The under part ot the drain, however, (liould be laid or 

 toupkd with Hones, as a canal to carry off the water fub- 

 fiding through the faggots ; and which has alfo the good 

 eftedt of prolonging their duration ; for when the water 

 cannot get off, which mult be the cafe where there is no 

 open conduit of ftones, its flagnation amongft the brancheg 

 muft foon caufe their decay, and choak up the paffage of 

 the drain. In no cafe whatever fhould the drain be filled 

 with Hones thrown in in a promilcuous manner, without a 

 courfe for tlie water at the bottom being firlt formed. 

 There is one thing more to be attended to in completely 

 accomplifliiiig the drainage of thefe foils : if the fiild liei 

 very much on the defcent, care mull be taken in laying out 

 the i/-i7nc/j-drains in a dire(ftion fufficiently horizontal, fo as 

 not to make the fall too precipitant, by which the bottom 

 of the trenches would be worn uneven, and this would ob- 

 ftruft the paffage of the water, which might foon blow 

 them up ; but the fall fhould be fuch as to enable the water 

 to clear its courfe. The reafon why fewer drains arc re- 

 quired in fields that lie nearly horizontal, as thofc of the 

 fecond kind here mentioned, is, that the water is drawn 

 equally from both fides, whereas thofe on a floping deeUvity, 

 drawing only from the liigher fides of the drain,^, require 

 them to be more in number, or clofer to one another. This 

 is the cafe in every fituation wiiere furface-draining is ne- 

 ceffary, and particularly fb in fome forts of foils, as will be 

 feen defcribcd in that kind of draining. See Sukface- 

 Dralning. 



In Lancafhire, where thefe foils, compofed of alternate 

 beds of clay and fand, very much predominate, and which 

 have there acquired the names oi fand-pots, or guts, a term 

 properly enough applied to them from their holding water 

 like a pot, it is obferved, that feveral drainages have been 

 executed by Mr. Elkington in the manner here defcribed, 

 and alfo a very difficult one of the fame kind at Sutton-Hall, 

 Derbyfhire, where the water was contained in fmall bedl 

 of rock, crofled and intercepted by beds of clay. 



There are flill other cafes of thefe intermixed foils, fuch 

 as thofc which have a porous, or partly impervious fuper- 

 ficial foil, while the undcr-ftrata are conltituted of different 

 diftinft mafles of impervious repellent materials, difpofed in 

 a regular manner. The lands which lie near ti'.e bottoms of 

 hills and flopes are often compofed of fuch impervious 

 maffes of the clayey, llrong marly, or lliff loamy kinds. 

 Such an intermixed, irregular conltrudtion of land, has natu- 

 rally the cffcft of forcing the intern.il water?, which defcend 

 from fprings in tlie higher grounds, as well as that which it 

 taken up by the furface-foil, where it is porou<, upwards 

 towards the furface of the lands, or other directions, io as to 

 caufe or induce wetneffes which liave different appearance*, 

 according to the nature or quality of the fuperficial parts of 

 fuch grounds, as wet, rufhy. fedgy, or other cold moid 

 lands, oozing, fpringy, wet lands, land-fprings, quagmu-es, 

 quickfands, and aftual fprings of water, cither of the tem- 

 porary or more permanent kinds, as the circumitances of the 

 feveral cafes may be. 



The means of draining fuch intermixed portions of wet 

 ground of this fpringy nature, although attended with forae 

 difficulty, IS moftly capable of being acconiuhfli'-d without 

 any very great trouble or expence; thi« i'; to be cffi ited by 

 cutting up frora the main condudting drain, which (houlU 

 always be carried through the moll depending malies, fmall 

 drains into the feparate upholding mafiis or flrata, at fuitr 

 able depths, fo as to find tiic waters which rcit upon them 

 4 K 2 aod 



