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An ACCOUNT of the DRAINAGE of a MARSH near MARAZION, in
CORNWALL, formerly overfiown by the Sea, and looked upon as irreclaimable, but now in a State of Cultivation.
(From the same Work.)
N purchasing the leasehold water had no other vent than
of an esate near Marazion, by its direct communication in Cornwall, confitting of about with the tea; and, two hundred acres, I found seventy “ Thirdly--That if the success in a state of good cultivation, and in the drainage should be equal one hundred and thirty acres of to my most sanguine expectawaste land, contisting of marsh, tions, yet the nature of marih croft, and fandy fcils. I flattered land, in general, would not myself, that a great part of this un- admit of any valuable inprofitable fpot might be converted provement. into ufeful and valuable land, “ however cogent these reasons which, in this neig! bourhood, in might appear to the public, I was the conmon state of cultivation, is convinced that they arose more worth from three to fix pounds the from the want of a spirit of enterCornih acre (about one-fifth part prile, and little knowledge of the larger than statute measure). From nature of such foils, than froia a a prospect of recovering that part decided conviction of the failure of called the Marsh, which had hither the plan; and, on considering the to been accounted irreclaimable, I advantages linely to result from the laid down a plan of draining the improvement, in case of success, and same, which, if I succeeded in, the example given to my country, might probably induce the proprie. men, who possess similar tracts of tors of other tracts of marthi land in marthland, I was emboldened to this vicinity, to make similar at- undertake the drainage of this.bog, tempts.
which for time immemorial had " The novelty of my draining been looked on as utterly irreclaimscheme, with its attendant ditticul- able. ties, joined to the great dislike “ The spot fixed on for the inwhich most farmers in the weft of tended improvement, contified of England have to the improvement fixty-three acres, statute measure; of low lands, drew on me the cen- of which thirty-lix acres were marshi; sure of the public, who treated the seventeen acres of a light blackish scheme as chimerical
, and impoffi- fand, and ten acres of croft, conble to be effected for the following fisting of a light black mould, with reasons:
a fubitratum near the
furface, of 1 “ First-Because the sea had ac- fine tenacious clay. The croft and
cess to this lavd, and overflow. fandy land lay on a rifing ground, ed it at spring tides with two serving as a surrounding skirting to
the marsh, and which, from their “ Secondly - If the sea were ex. gentle elevations, might be ufeful
cluded, the fresh water would in rainy seasons for cattle to refort
fertile foils consist of a combina-ficulty, which hitherto prevented tion of clay, fand, and vegetable even an attempt towards the drain. matter, in different proportions, ing this bog, arose from its being and that the fichree fubitances were under the level of the tea at springalmofi distinct, and to be procured tides; so that no deeper outlet could in any quantity from this improv. be procured than the river, which able tpot, it appeared probable supplied it with filt-water. Butą that, after a complete drainage was on confidering the nature of water, performed, little inore remained to which
presses equally on every fide, be effected, than a happy combina, I suspected that a pipe, with a valve tion of chele three fojis, fo conti- at its extremity, introduced at halfguous to each other, to render the ebb, through the fandy embank. whole good and productive land. ment, to the body of the marsh,
" The marsh, containing thirty- would tend to carry off the furfacefix acres, is situated between the water; and, from the frutting of croft and the fandy soil, which has the valve, on the approach of the been thrown up by the sea, and tide, no sea-water could gain ad. serves as a natural embankment mittance through the tube, On against the water, which at every taking an accurate survey of the spring-iide overflowed this law- levels from the sea, at the point of land to the height of two or three half-ebb, to the surface of the. feet, by a direct communication of ground in the marih, measuring in a river which carries off a part of length one hundred and seventythe redundant water collected on its four yards, it was found that fix furface, from its own springs and feet of level could be gained, after others in its vicinity, and the rain allowing tivo feet for the flowing from the higher grounds.
of the water through the pipe; ac" This marsh, frem time imme- cordingly, an embankment of one morial, has produced nothing but thousand one hundred and seventyrules, flags, gofs (arun to phragmi- five yards in length, formed of tis), nis palu ris, water-lily, and froog clav turf, about five feet high several other aquatic punts, which, and fix teet thick, was made round from their verdure, served only as the two sides of the rarth, which a decoy for catele, that were fre- were i able to be overtlown by the quently fmathered in attempting to sea ; the ditch serving as a channel reach them, to the great lots and to carry off the water, which used injury of the tenants. Several per- to tow over its surface. In order fons also have lost their lives by to carry off the water still remaingetting at night into this morals, ing on the marfii, I procured one over which boats have frequently hundred and seventy-four yards of palled to enable sportsmen to fe- square pipe, nine inches diameter cure the game, which flocked to and two inches thick, made or this place in great quantities during sound fir-wood called balk, which, winter. From the production of in the mines of this county, is the marsh miasmata, fevers of the low wood niott commonly made use of, nervous kind, but particularly a- and found to be very durable, espegues, have greatly prevailed, to the cially it kept constantly in water. annoyance and distress of the neigh- " In May, 1793, the first pipe bourhood.
was laid down on the shore, at the The great and unsuperable dif- point of half ebb, and secured by 9
means of a large rock, to prevent ceases to flow; and, during that it from swimming; the other pipes time, collects within the reiervoir were successively joined, and laid and trenches till the sea begins a. nearly on a plane with the first, by gain to retire; and when the col. throwing open the fand. As we lected water becomes of equal advanced to the highest part of the weight with the sea water over the sandy embankment, which was fhore pipe, it Ginks gradually till twenty-four feet above the pipes, the pipe is left by the sea, when it the difficulties were considerably regularly discharges the water strainincreased, by the great quantity of ed from the marth land; and which sand necessary to be removed, and amounts in winter to about i 29,600 its tendency to fall on the work- gallons, or 2160 hogtheads in twenmen; so that the approach towards ty-four hours; but, in summer, the the marsh became tedious, and very quantity is trifling, and does not expensive. However, by pursuing exceed 43,200 gallons or 720 hog. every cautious plan which could be meads. Some little difficulty at devised, to prevent accidents, and first arose from the valve not inut. to make the work secure, we arriv. ting itself properly, by the intrusion ed, in five weeks time, at the bor- of pebbles; but this was easily reders of the marsh, passing under moved, by adding about two feet the river and new-made embank- of pipe beyond the valve. ment at the depth of fix feet under Trenches or open drains of three the furface, where the pipe opened feet deep, five feet wide at the into a reservoir of eighteen feet top, and three at the bottom, were square and eight feet deep, prepared immediately carried from the reser. to collect the surface-water, which voir, which was the lowest place, immediately flowed through the to the extreme parts of the marsh, pipe with great rapidity, and dif- on the sandy side, about 6x feet charged itself into the sea, till the within the new embankment, and whole of the ftagnant water was intersected by others at right an. taken off. - The aperture of the gles towards the croft, from fifty to sea-pipe had iron-bars placed be. leventy-two yards distance, accordfore it, to prevent the infinuation ing to the nature of the ground, of extraneous bodies, and also a dividing the whole into regular ob. valve made of strong wood, lined long fields, as in the plan; the wet. and hung with leather, and loaded ness of the soil, and the great diffiwith iron, to prevent it from swim- ' culty of procuring a firm footing ming at the approach of the tide, for the workmen, obliged them which always thut it so close as to to stand on pieces of timber, to eiñectually exclude the sea-water : complete those numerous drains, the pipe within the reservoir had which every day grew firmer; and also a similar valve, for the faine in a few weeks the soil became so parpose, near its extremity, which consolidated, as to admit of persons was covered with an iron grating, walking over it with tolerable fafe. to prevent the intrusion of roots, ty. In making these drains a por weeds, &c. that might probably of copper coins, containing about obliruct the pallage of the water. one thousand, was discovered at the
" As soon as the tide returns to depth of three feet from the sur. the pipe, which is uncovered fix face, which, on examination, aphours in twelve, the marshi water peared to belong to the emperor
Victorinus, who reigned in the form peat moss. The horizontal third century; these coins were position of the leaves and stenis, much injured by the corrosion of which are easily discovered in the the marine acid, but several were peat, is a strong prefumption of still perfect enough to trace the those bodies having fallen down, outlines of the emperor.
and being buried by the constant 66 As soon as the evaporation af- accumulation of mud, which with sisted the consolidation of the sure the leaves are the component parts face, the air, within a mile of the of peat, though by fome it has been marsh, became so strongly impreg- said to be a vegetable production, nated with a fulphureous smell, as fui generis. The total exclusion of to render the place quite obnoxious air is absolutely necessary before to passengers, till the ground was these bodies will assume the real perfectly dry : this might probably appearance or properties of peat happen from the evaporation of the mofs; and it is probable, that the fluid parts, producing a decompo. upper stratum, which at this time sition in the mud, forming therein partakes of very little of real peat, a hepar Julphuris; or hepatic air may would at a future period, by the be easily produced, by adding sea gradual addition of similar bodies water to dung, or vegetable fub- and the exclusion of air, poffefs stances, from the vitriolic falts con- the same qualities and properties as tained in the water, and which pro. the under stratum, and by this grabably was the case in this soil.' In dual accumulation totally exclude the course of a few months the fur- the sea. But the coins found in face of the marsh was depressed the marsh indicate that the produc. from twelve to eighteen inches ; so tion of peat moss has been very that the bed of the river became flow in this particular spot. higher than the surface of the land. • The ftritum of fand under
“ In making the drains, it was the peat does not appear to be the discovered, that the upper stratum, original bed of the sea; for on of two feet and a half, consisted of streaming or searching for tin, from a dark-coloured mud, formed from fix to ten feeț deeper, another Strathe sediment of stagnant water and tum was discovered, consisting of a peaty substance, bound firmly to- round finooth pebbles and gravelly gether by an infinite number of the substances containing tin; among gofs and rush roots; the substra- which are bodies of trees, and a tum, an entire body of peat three large number of hazel-nuts in the feet and an half deep, of which most perfect state, and which must twenty-one inches are of a very hare been collected in this place by black colour, and the lowest part means of some extraordinary inun, of a light brownish or deep yel. dation, that swept those beds away low ; under the peat lies a stratum from the higher lands. of sand about five feet deep, which, “ In confequence of the discocarries evident marks of its being very of peat in this marih, a large the bed of the sea, of a very ancient quantity has been cut up, dried, date, and which has been gradually and made use of as an article of excluded by means of the accumu- fuel. for a variety of purposes, to lation of muddy sediments, and the which it is admirably adapted, and dropping of the leaves, &c. of a. sold at a much cheaper rate than quatic plants; and which together coals, and boils water in much lefs time; it is applied in public brew- which were also repeated in 1795, eries, and for every culinary pur- the ground became considerably prse as an article of fuel; it is made depressed and so confolidated as to life of to great advantage in grates, admit of carts with narrow wheels, hearths, or ovens, and, when coak- loaded with a ton of clay to pafs ed, will serve for the nicest ope- over it with great ease. On the ration in chemistry, and in that fides of the drains, large quantities state is fufficiently strong to smelt of yellow sea salt may be collected, metals of the most dificult fusion: and which were produced by the experiments are now making on it evaporation of its ituid parts. to calcine lime, which is intended as * In the spring of 1794, four manure for this land. This peat acres of ofiers were planted, after produces a small quantity of red the ground had been thrown up athes, which, on lixiviation, are into ridges; but the large quantity found to contain a large proporiion of sea-falt destroyed the whole, of fea falt, which, for land not al- except a few which grew on the ready impregnated with the marine higher ground in great luxuriancy. acid, will prove a valuable ma- The oliers at first put forth fine nure.
shoots; but as foon as their tender “ After the drains were finished, roots absorbed the saline particles in all further operations on this land the soil, they died immediately. Powere discontinued till the spring of tatoes were also planted in large 1794, when the surface of a great quantities the fame season; but many acres, consisting of light most of them, particularly in the fedgy fubfiances, was pared and low places, where they never vegeburned during the summer, and the tated, shared the same fase. alhes spread over the land; after- " On enquiry I find that those wards the plough was introduced, farmers who lay large quantities on to destroy the amazing growth of their piles (heaps) of manure, exthe aruncho phragn.iris, which, from perience the same lofs on thefe (pots the infinite number of its strong for two or three years afterwards; spreading roots, bound the surface and then the ground assumes the 10 firmly together, as to require a richest state of vegetation. In the numerous team of cattle to plough spring of 1795, after the surface it a proper depth, and which, from was covered with large quantities their frequent treading over the of clay, several acres were fowa same ground, rendered the soft parts with oats, some of which produced impatiable; but this difficulty was very good crops, particularly in overcome by ploughing the first those places where the marine acid time without a mould board, so was diminished. Turneps and pothat fewer oxen were able to per- tatoes also grew well. form the same work. The soil, on “ At prefent, the port trivialis being turned up, yielded a moft grows naturally in the greatest lux. offensive smell, though not of the uriancy on every part where the sulphur kind. The land was fre- faline particles are not in too large quently ploughed and harrowed, a quantity: the appearance of this even to qx or seven times, the in: grass is a sure indication of the soil Hammable substances set on fire, having parted with a large propor. and the ashes spread on the sur- tion of the falt. Several forts of face. After all'these operations, cultivated grafies have been tried in