EMB

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EMB

°f tu a ? then built. This forms a mound, on the outside# te pip k e > °f 15 or 16 feet broad ; and through this thereVs „| ^id, to carry off the sink-water. A stream of waterc &ti a j 8 °, . turne< l by the west end of the farm, by cutting a^hich conveyed the water through the embankment'fee i’ .y means of an outlet built of stone, with a sluice onSlc *e, raised to the level of the running water, and aon the outside, to be shut by the spring-tides.Vt er Place, a road, that formerly led to Findhorn at lowV &)»].• Ou oh the carse, is carried over the top of the dike,typfn ln g a mound of earth at each side, with a gradualIn 'p. and descent.

*>Hi 3 l le $ Ure a ) is the breadth of the dike at the top, when

W the breadth of dike at the bottom, being twelve

higij. en it is six feet high ; c, the breadth when eight feetV-i.Pj ’ the breadth when ten feet high ; f the slope on theth e e , 0 ^ the dike, which is always equal to half of the breadth

\ bott '

VnJ*’ 1s equal to the other half: and e is the plumb-rule inof «ie, - • -

tom : the inside slope, and breadth of the dike at

't w' Inade to apply to the mould or dike : the intentionHe re as > to find if the dike was kept on the proper slope,58 in a a lrie could not be applied from one mould to another,Hpt, r ° u nd or turn, or when the moulds were obliged to beSth ° Wn ; but this one only answered for the sea-side,V al ^ng used for the inside, to fit its slope.” Figure 21,i ^ tbe mould, one-eighth of an inch to a foot.

Jfc and' 0118 ’ use f u i> an( l highly ingenious method of embank-Preventing the waters of the tides from soaking1 the porous banks, made in the fen-lands, and low< 0l> rth founds, was described by Mr. John Smith, in thewl Ume of “ Communications to the Board of Agricul-H of ,!° begins by “ concisely observing, that the greatof ,j* e tens is divided into three large levels ; and that|M S . , tlesf! levels is subdivided into numerous districts bythese banks are made of fen-moor, and other£ a^y eri als, whenever the rivers are swelled with water,or 6r d ' str * ct is deluged either by rain, a breach ofj an y other cause, the waters speedily pass through

> j. t> moory, porous banks, and drown all the circum-tli OOO Stncts ' The fens have thus sometimes sustainedtw 6 aoo°, r ^^,000 damages by a breach of the banks, thoughoents seldom happen in the same district twice inyears. The water, however, soaks through all fen-8 w. year > every district ; and when the water-

J *11 V.W1 j uiotiiV/t 9 twiu »»ucti uio

111 ' ^itid '” ed f b e waters up out of the fens into the rivers4 ® p 0ro / da y, a great part of the water soaks back through^4 he 8 b£ mks, in the night, upon the same land again.”djNg ds > that “ this water that soaks through the bankV 8 ’ dost 6 wbeat in the winter, washes the manure into theth e 'f'^ 8 tbe best natural and artificial grasses, and pre-y's 6,18 ^ rom being sown till too late in the season,

tlif 8 > ant , Water lying on the surface, causes also fen-

? a 6h tt' -ibus, says he, the waters that have soaked

tf ih: 16

r' lfl jur" e P° I 0US fen-banks have done the fertile fens more'?V’ y all the other floods that have ever come upon

Vii

lie\^ 6en muc b concerned in fen-banking from his^' s to „ ad some time since devised the plan which he nowh/j5etiti' SWer so well ; but found it difficult to prevail withi t mai ?> who had a proper extent of this sort of land,Mi ,Va *l&d t faip tr ' a l- However, during the last autumn, he.V s| u n _ a person in the parish where he lives to try it,k. '‘lie W, “ J

i t to e q lia j t 0 his highest expectations

- P^Ved method Of emhonVi’n tr nrnnnspd h\)

ii' r ,^° ns ' sts chiefly in this : that

embanking proposed by thisa gutter is cut

let! g . c les wide, through the old bank down to the claystratum being generally clay;) the gutter is made5 P

near the centre, but a little on the land-side of the centre ofthe old bank. This gutter is afterwards filled up in a verysolid manner with tempered clay; and to make the clay resistthe water, a man in boots always treads the clay as the gutteris filled up. As the fen-moor lies on clay, the whole expenseof this cheap, improved, and durable mode of waterproofbanking costs in the fens only sixpence per yard. This planwas tried on a convenient farm, and a hundred acres of wheatwere sown on the land. The wheat and grass lands on thisfarm were all dry, whilst the fens around were covered withwater. This practice is, after all, nothing more than makinga puddle-bank, well known to all engineers, or those engagedin forming canals.

The term embankment in canal-making is applied to anylarge mound of earth, either for confining the water of thecanal or reservoir, or for carrying the former across a valleyor low piece of ground. The method of constructing suchembankments is nearly the same as in those for railways,except that in the former the sides have puddle-trenchesformed near the canal, to prevent leakage.

The embankments on some of the great lines of railway inthis country are of immense magnitude, on the London andBirmingham railway, for instance, the total of embankmentsamounted to about 11 millions of cubic yards. The follow-ing extracts from specifications for works of this kind willshow the usual mode of construction.

“ The whole of the embankments in this contract shall haveslopes of two to one (that is to say) where the base of theslope is two feet, its height shall be one foot only, and theyshall be thirty-three feet wide at the level of the red linein the section, neither more or less.

“ Each of the embankments shall be uniformly carriedforward as nearly as the finished heights and width as the dueallowance for shrinking of materials will admit of, and thisallowance shall not exceed or fall short of the quantity deemednecessary by the engineer. In all cases, this must be care-fully and strictly attended to, in order to avoid the necessityof making any subsequent addition, either to heights, or thewidth of the embankment, to bring them to their properlevel and dimensions.

, “The surface of the embankment shall be kept in such form,or be intersected by such drains, as will always prevent theformation of pools of water upon them, and insure theembankment being kept as dry as possible.

“ Whenever the material, teemed over the end of theembankment, shall not form the proper slope, it shall be care-fully trimmed to its required form ; and this operation mustproceed at the same time with the end of the embankment,so as to obviate the necessity of any future addition ofmaterial to the sides of the embankment.

“ As the embankments advance, and become consolidated,the slopes shall be carefully trimmed into planes having theproper slope, and be neatly covered with a uniform substanceof turf, of not less than eight inches in thickness, and laidwith the green sward outwards ; the turf must be taken fromthe ground to be occupied by the base of the embankment,and cut square, so as to be laid on the slopes in the form offlags ; and where the land is arable, the slopes of theembankment shall be covered with soil. It must be uni-formly laid on, of the thickness of six inches, and sown withrye-grass and clover-seed, as soon as the proper season willadmit of its being done, not less than one pound and a halfof clover seed, and one pound and a half of rye grass seed, tobe sown to each acre.

“ When the material, brought to the embankment, consistsof large lumps, they shall be broken into pieces of not morethan six inches in diameter.”

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